RU2183841C1 - Method of laser location and laser location device for its implementation - Google Patents

Abstract

FIELD: laser location, quantum electronics. SUBSTANCE: technical result lies in increased efficiency and range of laser location system, raised sensitivity in reception of weak optical signals with great length of pulse to level of sensitivity limited by quantum limit, enhanced probability of detection and reception of single-photon pulse signals, realization of high noise immunity against background radiation and interference with threshold level of noise exceeding spectral brightness of solar radiation. This technical result is achieved by formation of signal-analog of received radiation after spectral selection and amplification of received radiation with the aid of active quantum filter. Statistical parameters of radiation across output of active quantum filter are measured by means of active quantum filter in each partial spatial angle of reception. Value of function of deviation of statistical parameters from average value is found, cross correlation of signal-analog of received radiation and deviation function and summary value of function of deviation in observation interval are determined. Obtained values are compared with threshold level. EFFECT: improved functional capabilities of method and laser location device. 18 cl, 16 dwg

Description

 The invention relates to laser ranging and long-range laser communications. The preferred field of use of the invention is laser location systems for detecting and recognizing remote air and space small objects with an extremely small effective reflective surface.

 To detect small-sized distant objects by means of radio and laser location, the most important problem is the task of increasing the efficiency and range of location systems. This problem is solved by increasing the sensitivity of the receiving device and increasing the energy in the probe signal emitted by the transmitter. The possibilities of increasing the sensitivity of the receiving device are limited by a quantum limit due to the quantum nature of electromagnetic radiation. An increase in the energy of the probe radiation generated by the transmitter, when using pulsed signals with a short duration, leads to an increase in the transmitter power, which also has a physical limit due to the radiation resistance of the optical and antenna feeder systems, the possibility of breakdown and self-focusing of high-power radiation.

There is a method of increasing the efficiency of a radar system [1-6], based on the use of a radiated probe signal with a long duration T and limited power P _s . The energy of the probe signal E _{c is} proportional to its duration T: E _c = P _s • T (P _c = const).

где χ - коэффициент ослабления излучения зондирующего сигнала, определяемый дальностью до объекта и характеристиками его отражающей поверхности.In the receiving device (PU), optimal processing of the sounding electromagnetic signal reflected from the object [7] is carried out, the energy of which at the input of the PU is

where χ is the attenuation coefficient of the radiation of the probe signal, determined by the distance to the object and the characteristics of its reflective surface.

When using the optimal processing of the received signal [7], the value D of the signal-to-noise ratio at the output of the receiving device is equal to D = E _cw / G _o , where G _o is the spectral density of the noise power at the input of the control unit.

из (2) можно получить допустимую величину ослабления χ зондирующего сигнала при условии его достоверного обнаружения для данных параметров локационной системы (ЛС)

Реализуемая величина возможного ослабления излучения зондирующего сигнала χ определяет предельную дальность действия РЛС и характеризует эффективность РЛС.The value of D characterizes the radar efficiency and noise immunity of the controllers with respect to the additive interference acting on the input of the control panel and the own noise of the control panel. For additive noise such as "white noise" with an interference power P _p = G _o • F uniformly distributed in the frequency band F of the spectrum of the received signal, the spectral density of the interference is G _o = P _p / F. The average power of the signal P _{with Bx} = E _svh / T, and the value of D is equal to:
D = E _svh / G _o = P _svh • F • T / P _pom = P _svh • B / P _pom (1)
In relation (1), the value of P _cx characterizes the sensitivity of the control unit, equal to the power of the minimum detectable signal at the input of the control unit; the value FT = B is the base of the probe signal, characterized by the product of the signal duration by the width of its spectrum F. For reliable signal detection, it is sufficient to realize the signal-to-noise ratio equal to D = D _o > 2 at the output of the signal source. Then the level of the minimum detectable signal from (1) is equal to
P _svh = P _p • D _o / B = P _p • 2 / FT (2)
Taking into account

from (2) it is possible to obtain a valid attenuation value χ of the probe signal provided that it is reliably detected for these parameters of the location system (LS)

The realized value of the possible attenuation of the radiation of the probe signal χ determines the ultimate range of the radar and characterizes the effectiveness of the radar.

Thus, in the known method, increasing the efficiency of the location system χ (3) is realized by increasing the base B = FT of complex probing signals and performing special optimal processing of the received signal reflected from the object [7]. The essence of the optimal processing in the classical version [1-7] consists in using the matched filtering of the input signal or in the correlation processing of the input signal. In the first case, a matched filtering of the input signal E _{CBX is used} , in which the signal reflected from the object is passed through a matched filter, the parameters of which are consistent with the parameters and the shape of the probe signal emitted by the transmitter.

 In the second case, optimal processing is realized by forming a cross-correlation function between an exact copy of the probe signal and the received signal. As a result of optimal processing, the maximum signal-to-noise ratio D is realized at the output of the control panel, which improves the efficiency of the location system. Both options for the implementation of optimal processing are mathematically equivalent and differ in one feature: for the implementation of optimal processing of location signals, it is necessary to know an exact copy of the parameters and shape of the emitted sounding signal with the base B = FT and to save the parameters and shape of this signal at the input of the receiving device after reflecting the probe radiation from object and spread along the highway to the object and back. The presence of such a condition for implementing optimal processing of location signals with a large base of B = FT is a disadvantage of the known method for receiving location signals. This disadvantage is due to the fact that with a significant attenuation of the probe signal along the propagation path and, accordingly, at low levels of the received signal at the input of the transmitter, the initial shape of the probe signal is distorted, and the parameters generally change. In this case, the signal-to-noise ratio D (1) at the control unit output decreases and tends to zero, which leads to the impossibility of detecting objects at long range and to a decrease in the efficiency of the location system. This is especially characteristic of a laser location, in which, due to the quantum structure of the light field, a significant distortion of the initial shape of the probe signal (for example, a long pulse) occurs, in which separate groups of photons or single photons arrive at the input of the PU, and the original shape (structure) of the probe signal is completely or partially lost. Therefore, the direct use of the classical method of optimal processing of location signals using cross-correlation processing or matched filtering in the laser location and in the optical and infrared wavelength ranges is ineffective or completely impossible.

 The known method [6] of increasing the efficiency and resolution of radar systems is based on the use of a frequency-modulated pulse sounding signal and differs in that the reflected pulse is received in the receiving device using a shortening (matched) optimal filter, matched to the sounding parameters, made in the form delay lines with a linear dependence of the delay time on the frequency. The disadvantages of this method include a decrease in the sensitivity of the receiving device and a decrease in the efficiency and range of the location system while reducing the intensity of the received signal to a quantum level at which the shape of the original probe pulse signal is distorted or completely lost at the input of the receiving device. At the same time, at low levels of the input signal reflected from the object, the efficiency of the matched optimal filtering with the help of a shortening matched filter sharply decreases and does not provide the ability to operate the location system at a long range and for small objects.

A known method for the optimal processing of laser location signals [8], based on the irradiation of an object by a probe pulse signal with a duration τ _and dividing the observation interval T equal to the signal duration τ _and , into a number of sub-intervals, counting one-electron signal pulses and noise on each sub-interval τ _i by the energy input of the photodetector (photodetector) of count is multiplied by the weighting coefficients determined by the expected values of averages of signal and noise n _with n _w photoelectrons podinterv If τ _i , the obtained samples are summarized, and the sum is compared with a threshold value and, when the sum of the threshold value is exceeded, a decision is made on the presence of an object in the corresponding range cell. The disadvantages of this method include the low sensitivity and low efficiency of the location system at low levels of the received signal at the input of the receiving device, approaching the level of several quanta, due to the impossibility of accurate knowledge of the weight coefficients for the optimal count of signal and noise photoelectrons. These weighting coefficients are unknown values in the same way as the signal shape at the input of the receiving device is unknown, which is determined by the distribution of the numbers of signal photons n _with within the envelope of the pulse sounding signal reflected from the object and fed to the input of the receiving device. The distortion and loss of information about the shape of the received signal at the input of the receiving device is due to the quantum structure of the optical signal. This is due to the low efficiency of the optimal processing of laser location signals based on information about the shape of the pulse signal at the input of the receiving device and the distribution of weight coefficients associated with this form. It should be noted that the sensitivity of this method for processing location signals is limited by the sensitivity of the photodetectors used and does not allow the quantum limit of sensitivity to be realized, i.e. register single-photon signals.

The closest in technical essence to the proposed technical solution is the method of laser location [9], selected as a prototype. This method consists in generating laser radiation, illuminating the object with it, receiving radiation reflected from the object, spectral selection and amplifying it at the working wavelength λ _slave using a spectral selector — an active quantum filter (ACF), determining the spatial angle of reception of optical radiation reflected from object, and radiation at the output of the ACF, dividing the radiation flux into partial fluxes, setting the spatial partial angle of reception of each of the partial fluxes of radiation, equal the diffraction angle of receiving signals at the output of the ACF, the direction of each of the partial radiation fluxes to the corresponding partial photosensitive element of the multi-element matrix photodetector, measuring the average level of fluctuation of spontaneous radiation in one of the spatial partial angles of reception at the output of the ACF, setting the operating mode of the ACF at which the average level fluctuations of spontaneous radiation at the input of the ACF is minimal, deciding on the presence of an object based on a comparison of the levels of optical signals at the output of the ACF with a threshold level.

Как показано в [9], при использовании импульсных оптических сигналов с большой длительностью τ_имп≫ τ_к чувствительность ПУ уменьшается в несколько раз по сравнению с предельной квантовой чувствительностью, реализуемой при использовании импульсных сигналов с короткой длительностью. Это является недостатком данного способа, так как не позволяет повысить эффективность лазерной локационной системы единственно возможным оставшимся путем, а именно путем увеличения длительности зондирующего импульсного лазерного излучения и повышения общей энергии в лазерном импульсе, формируемом лазерным передатчиком при одновременной реализации предельной, технически возможной средней импульсной мощности лазерного передатчика.This laser location method, selected as a prototype, allows you to realize the ultimate quantum sensitivity of receiving signals reflected from the object, but only for laser pulses with a short duration τ _imp corresponding to the signal amplification band f _o in a quantum amplifier - active quantum filter (ACF)

As shown in [9], when using pulsed optical signals with a long duration τ _imp ≫ τ _{to the} sensitivity of the emitter decreases several times in comparison with the limiting quantum sensitivity realized when using pulsed signals with a short duration. This is a disadvantage of this method, since it does not allow to increase the efficiency of the laser location system by the only possible remaining way, namely by increasing the duration of the probe pulsed laser radiation and increasing the total energy in the laser pulse generated by the laser transmitter while simultaneously implementing the maximum technically possible average pulsed power laser transmitter.

 This drawback is due to the fact that in the known method [9], direct integration of the signal from the output of the photodetector is carried out within the time interval corresponding to the duration of the probe optical pulse signal. In this case, with a short signal duration, the ultimate quantum sensitivity is realized, and with an increase in the signal duration, the spontaneous noise of the quantum amplifier accumulates, which leads to a decrease in sensitivity compared to the reception of a short pulse.

 As a prototype for a device that implements the proposed method, the selected device that implements the prototype method [9].

 The proposed method allows to overcome the disadvantages of the known method of laser location [9] and to realize the reception of laser pulses of long duration at the level of ultimate quantum sensitivity.

 Achievable technical result is an increase in the efficiency and range of the laser location system, the implementation of extremely high quantum sensitivity of the reception of laser pulse signals with a long duration and high energy efficiency.

 The specified new technical result is achieved as follows.

1. In the known method, which consists in the formation of laser radiation, illuminating the object, receiving radiation reflected from the object, spectral selection and amplifying it at the working wavelength λ _slave using a spectral selector - an active quantum filter (ACF), dividing the radiation flux into partial streams, setting the spatial partial angle of reception of each of the partial radiation fluxes equal to the diffraction angle of receiving signals at the output of the ACF, the direction of each of the partial flows with the output ACF for the corresponding partial photosensitive element of a multi-element photodetector (MFP) and deciding on the presence of an object based on comparing the optical signals at the output of the ACF with a threshold level, simultaneously modulating the laser radiation, it is time-modulated, and an optical analog signal is generated based on the modulated laser radiation of the received radiation, determine its duration T _a , convert it into an electrical signal analogous to the received radiation and remember this signal -analogue through a memory unit, measure the statistical parameter of optical radiation at a working wavelength λ _slave in each partial spatial reception angle at the output of the ACF by analyzing the signals at the output of the MFP, determine the average value of the statistical parameter for all spatial partial reception angles at the output of the ACF, after this, during the reception of radiation reflected from the object, in each of the partial reception angles at the output of the ACF, the deviation of the statistical parameter from cf day value of this statistical parameter and generating deviation F function (t) in time equal to the difference of the current values of the statistical parameter and the mean value of the statistical parameter is performed the current time summation of values of the deviation F (t) over the time interval T _c, equal to the duration T _and optical signal-analogue of the received radiation, compare the received amount Z ₁ on the time interval T _with the first specified threshold level P ₁ , at the same time form a cross-correlation function K (t) between the stored electric signal-analogue of the received radiation and the generated deflection function F (t) on the time interval T _c equal to the duration T _{a of the} optical signal-analogue of the received radiation, the magnitude of the cross-correlation function K (t) is compared with the second given threshold level P _2, taking a decision on the presence of an object or when Z ₁ exceeds the sum of the first predetermined threshold level P ₁ or exceeded, K (t) value of cross-correlation functions of the second predetermined threshold level P _2, or concurrently nnom fulfilling both of these conditions in one or in several partial spatial angles reception output ACF.

2. The time-based modulation of the generated laser radiation is carried out by changing the absorption time of the optical radiation inside the resonator of the laser source at a working wavelength λ _slave over time, the law of the time-varying absorption value being set in accordance with the time-varying signal of the modulating generator.

где L - предполагаемая дальность до объекта;
Q - расходимость лазерного излучения, сформированного источником лазерного излучения для подсвета объекта;

- площадь входного зрачка (апертуры) приемного телескопа, D_Т - диаметр приемного телескопа;
S_oб - предполагаемая эффективная площадь отражающей поверхности объекта;
ε_об - предполагаемый коэффициент отражения излучения поверхностью объекта;
ε₂ - коэффициент пропускания излучения в атмосфере на рабочей длине волны λ_раб, равный ε₂ = exp[-α_п•L_a], где α_п - спектральный коэффициент поглощения излучения атмосферой для рабочей длины волны λ_раб, L_a - длина предполагаемого пути распространения излучения в атмосфере до объекта и в обратном направлении от объекта;
ε₃ - коэффициент пропускания излучения в атмосфере, обусловленный рассеиванием на неоднородностях атмосферы на рабочей длине волны λ_раб, равный ε₃ = exp[-α_p.м•L_a], где α_p.м - коэффициент молекулярного рассеивания излучения в атмосфере на рабочей длине волны λ_раб.3. The formation of the optical signal analogue of the received radiation is carried out by branching part of the generated and modulated laser radiation, the branch part of the radiation is Fourier transform and attenuate it χ times, and the attenuation coefficient χ is chosen in accordance with the formula

where L is the estimated range to the object;
Q is the divergence of the laser radiation generated by the laser source to illuminate the object;

- area of the entrance pupil (aperture) of the receiving telescope, D _Т - diameter of the receiving telescope;
S _about - the estimated effective area of the reflecting surface of the object;
ε _about - the estimated coefficient of reflection of radiation by the surface of the object;
ε ₂ is the transmittance of radiation in the atmosphere at a working wavelength λ _slave equal to ε ₂ = exp [-α _p • L _a ], where α _p is the spectral absorption coefficient of radiation by the atmosphere for a working wavelength λ _slave , L _a is the length of the assumed radiation propagation paths in the atmosphere to the object and in the opposite direction from the object;
ε ₃ is the transmittance of radiation in the atmosphere, due to scattering by inhomogeneities of the atmosphere at a working wavelength λ _slave , equal to ε ₃ = exp [-α _p.m • L _a ], where α _p.m is the coefficient of molecular scattering of radiation in the atmosphere by working wavelength λ _slave

 4. As a statistical parameter of optical radiation, the number of random emissions of the amplitude of the optical radiation per unit time over an arbitrarily chosen fixed level is used.

 5. As a statistical parameter of optical radiation, the total duration of random emissions of the amplitude of optical radiation per unit time over an arbitrarily chosen fixed level is used.

6. As a unit of time for measuring the statistical parameter of optical radiation, a period of time equal to or a multiple of the time constant of the active quantum filter ACF t _p inversely proportional to the value f _o of the quantum gain band ACF is used: t _p = 1 / f _o .

7. To form the values of the first and second predetermined threshold levels P ₁ and P ₂ , the generated optical signal analog of the received radiation is directed to the optical input of the ACF, subjected to spectral selection and amplification at the working wavelength λ of the _slave in the ACF, in each of the partial spatial angles receiving output ACF determine the statistical parameter of optical radiation at a working wavelength λ _slave , determine the average statistical parameter of optical radiation for all partial spatial angles receiving at the output of the ACF, in one of the partial reception angles corresponding to the angular direction of the optical signal analogue of the received radiation directed to the optical input of the ACF, determine the current time deviation of the statistical parameter of optical radiation from the average value of this statistical parameter as a function of time and form the deviation function F ₂ (t), equal to the difference between the current values S (t) of the statistical parameter and its average value S _о (F ₂ (t) = S (t) -S _о ), the current summation is performed in time changing the values of the deviation function F ₂ (t) over a time interval T _s equal to the duration of the generated signal-analog of the received radiation, the resulting sum Z _{2 is} taken as the value of the first predetermined threshold level P ₁ = Z ₂ , at the same time, a cross-correlation function K _{2 is formed} (t) between the stored electric-analog signal of the received radiation and the generated deflection function F ₂ (t) in the time interval Δt, equal to the duration T _c analogue signal received radiation Δt = T _c, the maximum value were determined ins cross-correlation function R ₂ (t) M ₂ = max {K ₂ (t)} and the resulting value M ₂ is taken as the second predetermined threshold level P ₂ = M _2.

8. In a known device containing a laser source installed on the first optical axis at a working wavelength λ _slave with a pump unit, a rotary mirror with a mirror drive and a mirror drive control unit, a receiving telescope mounted on the second optical axis, connected to the rotary mirror by an input, the first reflective mirror with a displacement unit, an active quantum filter (ACF) with a pumping and filling unit with a working substance, a concave mirror, a second reflective mirror, a polarizing filter, interference a signal filter, a multi-element photodetector (MFP) and an information processing unit, the outputs of which are connected to a pump unit for a laser source, a pump unit and an active quantum filter filled with a working substance, a control unit for a rotary mirror drive, and a unit for moving the first reflective mirror, a signal conditioning unit received radiation analogue, statistical parameter determination unit, correlation analysis unit, summing unit, first and second threshold blocks, first and second threshold level measuring units, a duration measuring unit, a memory unit, a modulating generator, wherein the optical input of the received radiation analog signal generating unit is optically coupled to the optical output of the laser radiation source through the first translucent mirror, the optical output of the received radiation analog signal generating unit is connected to optical input of the active quantum filter through the first reflective mirror, and the electrical output of the signal conditioning unit analogue pr of the received radiation is connected to the inputs of the memory unit and the duration determination unit, the outputs of which are respectively connected to the inputs of the correlation analysis unit and the information processing unit, the control input of the received-analog signal-generating unit is connected to the output of the information processing unit, the outputs of the multi-element photodetector are connected to the inputs of the determination unit statistical parameters, the control input of which is connected to the output of the information processing unit, and the outputs to the summing unit and to b correlation analysis, the control input of the summing unit is connected to the output of the information processing unit, and the output is connected to the first threshold unit and the first threshold level measurement unit, the output of which is connected to the first threshold unit, and the control input is connected to the output of the information processing unit, control input of the unit correlation analysis is connected to the output of the information processing unit, and the output is connected to the second threshold unit and the second threshold level measurement unit, the output of which is connected to oromu threshold unit, and a control input connected to the output information processing unit outputs the first and second thresholds blocks connected to inputs of an information processing unit, an output of the modulating oscillator connected to the laser source.

 9. The laser radiation source comprises optically coupled a first laser mirror of a laser radiation source cavity, an active laser element with a pump unit, a first polarizer, a laser modulation unit, a second polarizer and a second laser mirror of a laser source resonator located in series on the optical axis, wherein the laser modulation unit radiation is connected to the output of the modulating generator.

 10. The unit for generating a signal-analogue of the received radiation contains a third reflecting mirror, a Fourier transforming lens, a diaphragm, a radiation attenuation unit, a first forming lens, a second translucent mirror recording a photodetector, and a fourth reflecting one mounted on the optical axis from the optical input to the optical output of the unit a mirror, a second forming lens and a fifth reflective mirror, moreover, the control input of the radiation attenuation unit is connected to the information processing unit, and the output egistriruyuschego photodetector is connected to the memory block and the block determining duration.

 11. The unit for determining the statistical parameters contains cells for determining the parameters of the emissions by the number of partial elements in the multi-element photodetector, subtracting cells by the number of cells for determining the parameters of the emissions, the first clock generator, the first switch, the adder and the cell division, while the inputs of the cells for determining the parameters of the emissions are connected to the corresponding outputs partial photosensitive elements of a multi-element photodetector, and the outputs are connected to the inputs of the subtraction cells and the inputs of the first switch, the second inputs of the subtraction cells are connected to the output of the division cell, the output of the first switch through the adder is connected to the input of the division cell, the cells for determining the emission parameters are connected to the output of the first clock generator, the first clock generator and the cells for determining emission parameters are connected to the information processing unit, the control input of the first switch is connected to information processing unit.

 12. In the unit for determining statistical parameters, the cell for determining the parameters of emissions contains a series-connected amplitude selector, a shaper, first and second counters connected to a switch, a gating cascade and a generator of counting pulses, while the inputs of the gating cascade are connected to the outputs of the calculating pulse generator and the shaper, and the output is connected to the second counter, the control inputs of the amplitude selector and the first and second counters are connected to the output of the first clock generator, yuschy switch input connected to the output of the information processing unit.

 13. The summing unit contains the summing cells - according to the number of partial photosensitive elements in the multi-element photodetector, the second switch and the second clock generator, while the inputs of the summing cells are connected to the corresponding outputs of the subtraction cells of the statistical parameter determination unit, and the outputs are connected to the inputs of the second switch, the output of the second synchronizer connected to the control inputs of the summing cells, the output of the second switch, connected to the first threshold block and the first measurement block stratum level, the second clock control input connected to the output information processing unit, the control input of the second switch and the summing cells output connected to the information processing unit.

 14. In the summing unit, the summing cell contains a ring switch, memory registers, an output switch, an output adder and a control circuit, while the outputs of the ring switch through the memory registers are connected to the inputs of the output switch, the output of which is connected to the output adder, the control input of the ring switch through the circuit control is connected to the output of the information processing unit, and the control input of the output switch is connected to the output of the second clock.

 15. The correlation analysis unit contains correlators for the number of partial photosensitive elements in a multi-element photodetector and a third switch, the output of which is connected to the second threshold unit and the second threshold level measurement unit, while the inputs of the correlators are connected to the corresponding outputs of the subtraction cells of the statistical parameter determination unit, the second inputs correlators are connected to the output of the memory block, the outputs of the correlators are connected to the inputs of the third switch, the control input of which is connected It is ready for the output of the information processing unit.

 16. In the correlation analysis unit, the correlator comprises optically coupled light sources, a beam expander, an acousto-optic modulator, a first lens, a first spatial filter, a second lens, a light-modulating cathode ray tube (SELT), a third lens, and a second spatial filter, sequentially mounted on the optical axis a photodetector, the output of which is connected to an intermediate memory unit, as well as a ring switch, memory registers, an output switch, a control circuit, an intermediate frequency generator you and the amplifier, while the outputs of the ring switch through the memory registers are connected to the inputs of the output switch, the output of which through the intermediate frequency generator is connected to the control electrode of the acousto-optic modulator, and the control input to the information processing unit, the control input of the ring switch through the control circuit is connected to the output information processing unit, the SELT control electrode is connected through an amplifier to the output of the memory unit, the input of the ring switch is connected to the output of uyuschey subtraction unit cell determining statistical parameters, and the output of the intermediate storage unit is connected to the corresponding input of the third switch.

 17. In the correlation analysis unit, the correlator contains a ring switch, memory registers, an output switch, a control circuit, first, second and third fast Fourier transform (FFT) processors, a multiplier and a reference memory register, while the outputs of the ring switch are connected to the inputs through memory registers output switch, the output of which is connected to the input of the first FFT processor, and the control input is connected to the output of the information processing unit, the output of the first FFT processor is connected to the first input, multiply For, the output of the second FFT processor through the reference memory register is connected to the second input of the multiplier, the output of which is connected to the input of the third FFT processor, the output of which is connected to the corresponding input of the third switch, the input of the second FFT processor is connected to the output of the memory block, the control input of the ring switch through the circuit control is connected to the output of the information processing unit, and the input is connected to the corresponding subtraction cell of the unit for determining statistical parameters.

 18. The duration measurement unit contains an amplitude selector first and second shapers, first and second gate stages, first and second counters, a counting pulse generator, an inverter and an adder, the output of the amplitude selector connected to the input of the first shaper, the output of which is connected to the inverter and the first the gating cascade, the output of which through the first counter is connected to the first input of the adder, the output of the inverter through the second driver is connected to the input of the second gating cascade, the output of which through the second counter it is connected to the second input of the adder, the output of the counter pulse generator is connected to the second inputs of the first and second gate stages.

Designations of elements in the drawings
In FIG. 1 shows a block diagram of a laser location device that implements a method where the following notation is introduced:
1 - Laser source - laser generator.

 2 - Active laser element.

 2a - Pumping unit.

 3 and 4 - Mirror cavity of a laser source.

 5 - Block modulation of laser radiation.

 6, 7 - Polarizers.

 8 - Modulating generator.

 9 - The first translucent mirror.

 10 - Swivel mirror.

 11 - Drive and control unit of the rotary mirror.

 12, 13 - Receiving telescope.

 12 - The first mirror of the receiving telescope.

 13 - The second mirror of the receiving telescope.

 14 - The first reflective mirror.

 15 - Block movement.

 16 - Active quantum filter (ACF).

 17 - Block pumping ACF and filling with a working substance.

 18 - Concave mirror.

 19 - The second reflective mirror.

 20 - Polarizing filter.

 21 - Interference filter.

 22 - Multi-element photodetector (MFP).

 23 - Block definition of statistical parameters.

 24 - Block correlation analysis.

 25 - Block summation.

 26 - The first threshold block.

 27 - The second threshold block.

 28 - Information processing unit.

 29 - Block generating signal-analogue of the received radiation.

 30, 30a, 31 - the third, fourth and fifth reflective mirrors.

 32 - Fourier transform lens.

 33 - The first forming lens.

 34 - The second forming lens.

 35 - Aperture.

 36 - Block attenuation of radiation.

 37 - The second translucent mirror.

 38 - Recording photodetector.

 39 - Duration measurement unit.

 40 - Memory block.

 41 - The first block of measurement of the threshold level.

 42 - The second block of measurement of the threshold level.

 43 - Block-distributor of external target designation signals (VTsU) (not included in the device).

 Position 43a denotes external information consumers (VPI), which receives a detection signal and coordinate parameters of the observed object from the output of the information processing unit 28. The VPI 43a is not included in the composition of the device.

 In FIG. 2 shows a block diagram of the composition and connection of the block for determining statistical parameters 23, the block of correlation analysis 24, the block of summation 25.

Figure 2 introduced the following notation:
22 - Matrix photodetector (MFP).

 26 - The first threshold block.

 27 - The second threshold block.

 28 - Information processing unit.

 41 - The first block of measurement of the threshold level.

 42 - The second block of measurement of the threshold level.

 44 - Cells determine the parameters of emissions.

 45 - The first sync generator.

 46 - The first switch.

 47 - Adder.

 48 - Cell division.

 49 - Subtraction cells.

 50 - Summation cells.

 51 - The second switch.

 52 - The second clock generator.

 53 - Correlators.

 54 - The third switch.

Figure 3 presents a block diagram of a cell for determining the parameters of emissions, which introduced the following notation:
55 - Amplitude selector.

 56 - Shaper.

 57 - The first counter.

 58 - The second counter.

 58a - Switch.

 59 - Gating cascade.

 60 - Counting pulse generator.

 In FIG. 4 are oscillograms explaining the principle of operation of the cell for determining emission parameters in FIG. 3.

Figure 5 presents a block diagram of the summation cell (item 50 in figure 2), where the numbers denote the following elements:
61 - Ring switch.

 62 - Memory registers.

 63 - Output switch.

 64 - Output adder.

 65 - Management scheme.

 In FIG. 6 is a block diagram of a first embodiment of a correlator, item 53 in FIG. 2 (an optical information processing option).

The correlator 53 in Fig.6 contains the following elements:
66 - Ring switch.

 67 - Memory registers.

 68 - The output switch.

 69 - Management scheme.

 70 - Intermediate frequency generator.

 71 - Acousto-optic modulator.

 72 - Light source.

 73 - Beam expander.

 74 - The first lens.

 75 - The first spatial filter.

 76 - The second lens.

 77 - Light-modulating cathode ray tube (SELT).

 78 - The third lens.

 79 - The second spatial filter.

 80 - Photodetector.

 81 - Amplifier.

 82 - Intermediate memory block.

In FIG. 7 shows a block diagram of the correlator pos. 53 in figure 2 ( ^2nd embodiment, digital information processing).

In Fig.7 introduced the following notation:
91 - Ring switch.

 92 - Memory registers.

 93 - Output switch.

 94 - Management scheme.

 95, 96, 97 - The first, second, and third fast Fourier transform processors (FFT).

 98 - Multiplier.

 99 - Reference memory register.

 In FIG. 8 is a view of oscillograms explaining the operation of a signal generating unit analogous to received radiation.

In FIG. 9 is a block diagram of a duration measurement unit, pos. 39 in FIG. 1, where the following designations of input elements are introduced:
100 - Adder.

 101 - Amplitude selector.

 102 - The first shaper.

 103 - The first gating cascade.

 104 - The first counter.

 105 - Counting pulse generator.

 106 - Inverter.

 107 - The second shaper.

 108 - The second gating cascade.

 109 - The second counter.

 In FIG. 10 and 11 present the results of an experimental study of a device that implements the method.

 The principle of operation and implementation of the proposed method are as follows.

 According to the external target designation (TCU) from block 43, information processing unit 28 receives information about the expected angular coordinates of the object. According to the estimated angular coordinates of the object, the information block 28 generates commands received by the control unit 11 of the rotary mirror drive 10, as a result of which the latter is oriented in the direction of the intended location of the object.

A laser pulse is generated using a laser source 1 and the object is illuminated with a generated laser pulse at a working wavelength of λ _slave (λ _slave ). When the laser radiation is generated, it is modulated in time in accordance with the time change of the signal from the external modulating generator 8. The signal from the modulating generator 8 enters the laser radiation modulation unit 5, which provides a time-varying absorption value of the optical radiation inside the resonator of the laser generator source laser radiation 1. As a result, the generated laser radiation to illuminate the object becomes modulated in time for any Parameters such as amplitude.

 Based on the time-modulated laser radiation, an optical signal analogous to the received radiation is generated as follows, using the received signal analogue signal generating unit 29.

где d₂ - диаметр ФПЛ 32 и f_л - ее фокусное расстояние. В результате диафрагма 35 выделяет только ту часть лазерного излучения из всего распределения излучения в дальней зоне, которая отражается объектом, что обеспечивает полное и точное моделирование процесса подсвета объекта сформированным лазерным излучением и его отражение объектом. Далее осуществляют ослабление излучения в χ раз посредством блока ослабления излучения 36, который представляет собой набор сменных оптических фильтров с заданным параметром ослабления, устанавливаемых в оптическом тракте по командам от блока обработки информации 28.A part of the generated and modulated laser radiation is branched off from the output of the laser radiation source 1 by means of the first translucent mirror 9 and directed through the mirror 30 to the optical input of the Fourier transform lens 32 (FPL). The latter carries out the Fourier transform of the branched laser radiation and forms in the plane of the diaphragm 35, which is aligned with the focal plane of the FPL 32, a spatial signal equivalent to the spatial optical signal generated by the laser radiation source 1 in the far zone, i.e. in the plane of the observed object. The optical signal in the focal plane of the FPL 32, combined with the plane of the diaphragm 35, is a spatial Fourier spectrum of the distribution of laser radiation generated by the laser radiation source 1; the distribution of this Fourier spectrum is similar (on a reduced scale) to the distribution of laser radiation in the far zone in the region of the observation object. The diaphragm 35 selects from this radiation distribution the central part located on the axis and defining the region in which it is possible to find an object that causes the reflection of part of the laser radiation received back. The various side lobes of the diaphragm of the directivity of the laser radiation are not passed through the diaphragm 35, the size of d ₁ which is chosen smaller than the size of the diffraction scattering circle δ ₁ in the focal plane of the PL 32

where d ₂ is the diameter of the FPL 32 and f _l is its focal length. As a result, the diaphragm 35 selects only that part of the laser radiation from the entire radiation distribution in the far zone, which is reflected by the object, which provides a complete and accurate simulation of the process of illumination of the object by the generated laser radiation and its reflection by the object. Next, radiation is attenuated by a factor of χ by means of a radiation attenuation unit 36, which is a set of replaceable optical filters with a given attenuation parameter installed in the optical path by commands from the information processing unit 28.

где Е_изл - лазерное излучение, сформированное на выходе источника лазерного излучения 1;
Е_прин - принимаемое лазерное излучение.The attenuation coefficient of radiation χ is determined based on the following relationship:

where E _Iz - laser radiation generated at the output of the laser radiation source 1;
E _prin - received laser radiation.

соответствует коэффициенту пропускания излучения.Value

corresponds to the transmittance of radiation.

где L - предполагаемая дальность до объекта,
θ - расходимость лазерного излучения [рад], сформированного источником лазерного излучения 1;

площадь входного зрачка (апертуры) приемного телескопа 12 с диаметром = D_Т;
S_об, ε_об - предполагаемые параметры наблюдаемого объекта, устанавливаемые априорно:
S_об - предполагаемая эффективная площадь отражающей поверхности объекта;
ε_об - предполагаемый коэффициент отражения излучения поверхностью объекта;
ε₂ - коэффициент пропускания излучения в атмосфере на рабочей длине волны λ_раб, определяемый на основании соотношения:
ε₂ = exp[-α_п•L_a],
где α_п - спектральный коэффициент поглощения излучения атмосферой для рабочей длины волны λ_раб;
L_a - длина предполагаемого пути распространения излучения в атмосфере до объекта и в обратном направлении от объекта до приемного телескопа 12;
ε₃ - коэффициент пропускания излучения в атмосфере на рабочей длине волны λ_раб, обусловленный рассеиванием на неоднородностях атмосферы, определяемой на основании соотношения:
ε₃ = exp[-α_p.м•L_a],
где α_p.м - коэффициент молекулярного рассеивания излучения в атмосфере на рабочей длине волны λ_раб.
Таким образом, в соотношении для устанавливаемой величины ослабления χ учтены все факторы, обуславливающие уровень принимаемого оптического излучения на входе приемного телескопа 12, при обнаружении объекта с предполагаемыми параметрами S_об, ε_об и находящегося на некоторой предполагаемой дальности L.The radiation attenuation χ is set such that the level of the signal analogue of the received radiation E _A (t) at the input of the ACF 16 and at the input of the recording photodetector 38 corresponds to the average level of the real received optical signal reflected from the object and fed to the input of the receiving telescope 12 and beyond to the input of the ACF 16. For this, the attenuation coefficient χ is selected and set in accordance with the following formula:

where L is the estimated range to the object,
θ is the divergence of the laser radiation [rad] generated by the laser radiation source 1;

the area of the entrance pupil (aperture) of the receiving telescope 12 with a diameter = D _T ;
S _about , ε _about - the estimated parameters of the observed object, set a priori:
S _about - the estimated effective area of the reflecting surface of the object;
ε _about - the estimated coefficient of reflection of radiation by the surface of the object;
ε ₂ - transmittance of radiation in the atmosphere at a working wavelength λ _slave , determined on the basis of the ratio:
ε ₂ = exp [-α _p • L _a ],
where α _p is the spectral absorption coefficient of radiation by the atmosphere for the working wavelength λ _slave ;
L _a is the length of the estimated path of radiation in the atmosphere to the object and in the opposite direction from the object to the receiving telescope 12;
ε ₃ - transmittance of radiation in the atmosphere at a working wavelength λ _slave , due to scattering on inhomogeneities of the atmosphere, determined on the basis of the ratio:
ε ₃ = exp [-α _p.m • L _a ],
where α _p.m is the coefficient of molecular dispersion of radiation in the atmosphere at the working wavelength λ _slave .
Thus, in the ratio for the set attenuation value χ, all factors that determine the level of received optical radiation at the input of the receiving telescope 12 are taken into account when detecting an object with the estimated parameters S _о , ε _о and located at some assumed range L.

Establishment of the selected value of radiation attenuation χ is carried out in the radiation attenuation unit 36 by introducing into the optical path an interchangeable filter corresponding to the selected attenuation χ according to instructions from the information processing unit 28. In the latter, the value of χ is calculated by formula (5) based on a priori assumed data about the parameters of the object S _error, ε _error, the assumed distance to the object L, _and L to the intended route of radiation propagation in the atmosphere, and the coefficients of transmission of radiation in the atmosphere ε _2, ε _3, n beam based on the priori data about the atmospheric parameters α _p, α _p.m at the operating wavelength λ _slave. In this case, the atmospheric parameters α _p , α _{p m} at the working wavelength are obtained on the basis of, for example, reference data.

The values of L and L _a are obtained from an external target designation system (TCU) based on preliminary target designation data and the estimated parameters L and L _a received from the TCU in the information processing unit 28.

где Н_атм - средняя эффективная толщина атмосферы при наблюдении объекта в зените, составляющая по справочным данным ~ 20-25 км;
α - угол наблюдения объекта, отсчитываемый от зенита (угол места) и получаемый по данным внешнего предварительного целеуказания.The parameter L _a - the length of the proposed path of radiation in the atmosphere - is obtained, for example, based on the following formula:

where N _atm is the average effective thickness of the atmosphere when observing an object at the zenith, which, according to reference data, is ~ 20-25 km;
α is the viewing angle of the object, measured from the zenith (elevation angle) and obtained according to external preliminary target designation.

When observing an object at the zenith, α = 0.
The parameters S _t and Q are set based on the known data on the diameter D _{T of the} receiving telescope 12 and the divergence Q of the generated laser radiation in the laser radiation source 1. A priori data on the estimated parameters of the observed object are previously stored in the RAM of the information processing unit 28.

где χ - необходимое ослабление излучения согласно формуле (5);
n_осн - пропускание первого полупрозрачного зеркала 9 в направлении основного канала для подсвета объекта;
n_ан - пропускание полупрозрачного зеркала 9 в направлении на вход блока формирования сигнала-аналога поз.29.When setting the χ value, the transmission parameters of the first and second translucent mirrors 9 and 37 are taken into account. As a result, the final value for the attenuation filter parameters β ₀ in the radiation attenuation unit 36 is set in accordance with the following formula:

where χ is the necessary attenuation of radiation according to formula (5);
n _main - transmission of the first translucent mirror 9 in the direction of the main channel to illuminate the object;
n _AN - transmittance of a translucent mirror 9 in the direction of the input of the signal forming unit of the analogue pos.29.

 The coefficient (1/2) in formula (7) takes into account the attenuation of radiation by the second translucent mirror 37, which has the same 50% transmittance for both of its output directions.

In the information processing unit 28, on the basis of the formula for β ₀ (7), the necessary attenuation parameter β ₀ is calculated for the attenuation filter in the radiation attenuation unit 36 and a command is generated to install a filter with this parameter β ₀ in the optical path in block 36.

As a result of the attenuation of radiation by β ₀ times in block 36 at the output of block 29, an optical signal is received that is analogous to the received radiation E _A (t), which is a model (analog) of optical radiation received by receiving telescope 12 in the presence of an object in the observed far zone, and reflection of illuminated laser radiation by this object.

In this case, the parameters of this optical radiation (signal) correspond to the reflection of laser radiation from some reference object with a priori established reference characteristics of radiation reflection and located at a priori established assumed range L. This optical signal formed at the input of photodetector 38 is taken as an optical signal analogous to the received radiation E _A (t). By registering the photodetector 38, the optical analog signal E _A (t) is converted into an electrical signal analogous to the received radiation E _AE (t), which is recorded in the memory unit 40 and is then used as a reference when detecting an optical signal reflected from the object. In this case, the analog signal E _A (t) is not an exact copy of the laser radiation generated by the laser generator 1 at its input, since during its formation, the radiation generated in the far zone is propagated during the propagation of radiation to the object, and the attenuation of radiation is also taken into account, due to the distance to the object and additional factors associated with the a priori assumed characteristics of the object. A part of the generated optical signal-analogue of the received radiation E _A (t) is sent using the second translucent mirror 37, the mirrors 30a and 31 and the second forming lens 34 to the input of the ACF 16 and is used to generate threshold levels P ₁ and P ₂ (see below )

и регистрируют сформированный при данном ослаблении χ₃ оптический сигнал-аналог с помощью РФ 38. В результате реализуют уравнивание величин интенсивностей предполагаемого реального оптического сигнала, поступающего на вход АКФ 16 от объекта, и модельного оптического сигнала-аналога принимаемого излучения Е_А(t), регистрируемого в РФ 38.As a recording photodetector (RF) 38, for example, a photodetector unit consisting of a series-optically coupled active quantum filter (optional) and a single-site photodetector can be used. The sensitivity of such an RF will be equal to the sensitivity of the actual ACF 16, which will determine the equivalence of the operations of receiving optical signals directly using the ACF 16 and receiving the generated optical analog signal E _A (t) using a recording photodetector 38. When using a 38 photodetector with sensitivity as the RF for example, m times less than the sensitivity of ACF 16, the attenuation coefficient of radiation β ₀ in block 36 is set respectively m times less than with equal sensitivity of the RF 38 and ACF 16 , i.e. set the attenuation coefficient of radiation χ ₃ in block 36 equal

and register the optical analog signal formed at this attenuation χ ₃ using RF 38. As a result, the intensities of the expected real optical signal supplied to the input of the ACF 16 from the object are equalized and the model optical signal analog of the received radiation E _A (t), registered in the Russian Federation 38.

After the formation of the signal analogue of the received radiation E _A (t) measure its duration (T _a ). To do this, the analog signal E _AE (t) from the output of the recording photodetector 38 is fed to the input of the duration measuring unit 39, which performs the operation of measuring the duration of the analog signal E _AE (t) arriving at its input. The measured parameter of the duration of the analog signal T _a then comes from the output of the duration measurement unit 39 to the information processing unit 28 and through it to the summing unit 25 and the correlation processing unit 24, where it is used to establish (set) the time interval T _s within which detection of an optical signal reflected from the object.

отсюда

где D₂ - диаметр АКФ 16;
f_л - фокусное расстояние вогнутого зеркала 18.The optical signal reflected from the object is received using a rotary mirror 10 and a receiving telescope 12, 13, consisting of two mirrors. During the reception of signals reflected from the object, the first reflective mirror 14 by means of the movement unit 15 is set to position P1 - the main working position. In position P2, mirror 14 is set at the time the threshold levels P ₁ , P ₂ are generated and the generated signal analogous to the received radiation is fed to the optical input of the ACF 16. The active quantum filter (ACF) 16 performs spectral selection and amplification of the optical signal reflected from the object by working wavelength λ _slave Spectral selection in a narrow reception band Δν on λ the _{slave is} carried out in ACF 16 by quantum amplification of the optical radiation passing through the ACF reflected from the object within the reception band of ACF Δν. The gain of the ACF K _y within its band Δν reaches significant values of K _y = 10 ³ -10 ⁴ . Optical radiation outside the quantum gain band Δν passes through ACF 16 without change. As a result, spectral selection of optical radiation is achieved with a high degree of radiation suppression outside the Δν reception band due to a significant amplification of the radiation falling into the Δν reception band and the absence of radiation amplification outside the Δν band.
The amplified and spectrally selected radiation from the output of the ACF 16 enters the concave mirror 18, which acts as a focusing lens of the reflective design. In the focus of the concave mirror 18 is installed a photosensitive platform MFP 22. The reflective mirror 19 is used to change the direction of the rays. The polarization filter 20 serves to isolate radiation of a single polarization, similar to the polarization of the probe laser radiation generated by the laser generator 1, and at the same time to reduce the intensity of spontaneous noise ACF 16. The interference filter 21 suppresses background light noise lying outside the gain band Δν ACF 16. Multi-element photodetector (MFP) 22 registers optical radiation at the output of the ACF 16 in separate partial reception channels, the number of which M ₁ corresponds to the number of partial of photosensitive elements in the MFP: M ₁ = N _fp • N _fp = N _fp ² , where N _fp is the number of elements in the same row of the square MFP 22. Each partial photosensitive element of the MFP 22 has a diameter of 2r and registers optical radiation from the output of the ACF 16 within the appropriate spatial angle of radiation reception ω _pr , the value of which is set equal to the diffraction reception angle at the output of the ACF 22. The separation of the radiation stream into separate partial streams is thus carried out by using a multi-element photodetector MFP 22, each partial element of which registers radiation from the output of the ACF 16 within the spatial (solid) partial receiving angle ω _pr equal to the diffraction angle ω _d . To implement the latter condition, the size r of one photosensitive partial element in the MFP 22 is selected from the condition

from here

where D ₂ is the diameter of the ACF 16;
f _l - the focal length of the concave mirror 18.

The fulfillment of these conditions (8), (9) is necessary to minimize the intrinsic noise of the ACF 16. Next, to determine the presence of the object and its detection, the statistical parameter of the optical radiation from the output of the ACF 22 is determined in separate partial reception angles ω _p at the output of the ACF 22.

The determination of the statistical parameter of optical radiation is carried out using the unit for determining the statistical parameters of pos. 23 in FIGS. 1 and 2. In each individual partial receiving angle ω _p corresponding to the partial element of the MFP 22, a measurement of the statistical parameter of optical radiation is carried out separately and independent of other partial elements . Each partial element of the MFP 22 converts the optical radiation entering its photosensitive area into an electrical signal, which is amplified by an individual electronic amplifier, which is part of each partial photosensitive element of the MFP, which forms one individual partial channel for receiving optical radiation from the output of the ACF 16. Next, determine the statistical optical radiation parameters is carried out by determining the statistical parameters of the electrical signals at the outputs of the MFP 22. El ktrichesky signal output from each of the partial photosensitive elements MFP 22 is input to determine the emission parameters 44 (Figures 2 and 3) of the corresponding cell. Cells 44 perform the function of the main measuring tool that determines the current statistical characteristics (parameters) of a random process at the output of each partial photosensitive element MFP 22 and, accordingly, each partial reception angle at the output of ACF 16. As the statistical parameter of optical radiation, the number of random emissions of the optical radiation amplitude in unit of time over an arbitrarily chosen fixed level.

 In the second embodiment of the method, the total duration of random emissions of the amplitude of the optical radiation per unit time over an arbitrarily chosen fixed level is used as a statistical parameter of optical radiation.

The following characteristics of the random process can also be used as a measured statistical parameter of a random process at the output of ACF 16:
- the average duration of emissions of random processes,
- amplitude of emissions,
- emission area,
- the duration of the intervals between adjacent emission extremes, and other characteristics of random processes.

The choice of the type of the measured statistical parameter is determined by the specific operating conditions of the radar in a real interference environment and the nature of the fluctuation of the signals reflected from the object. As a unit of time when measuring the statistical parameter of optical radiation, a period of time equal to or a multiple of the ACF time constant of 16 t _p is inversely proportional to the value of _o ACF quantum gain band t _p = 1 / f _o .

, соотношением f₀ = cΔν, где с - скорость света.The magnitude of the ACF quantum gain band f _о [Hz] is related to the magnitude of the gain band Δν, expressed in

, by the relation f ₀ = cΔν, where c is the speed of light.

соответствующее собственной постоянной времени АКФ. При этом наличие даже одного внешнего кванта (фотона) излучения на входе АКФ 16 вызывает существенное изменение статистических параметров (характеристик) случайного (спонтанного) излучения на выходе АКФ 16, а именно: увеличение количества случайных выбросов амплитуды оптического излучения в единицу времени, увеличение суммарной длительности случайных выбросов амплитуды оптического излучения в единицу времени. Для обнаружения отдельных квантов (фотонов) принимаемого оптического сигнала, поступающего на вход АКФ 16, осуществляют измерение статистических параметров оптического излучения на выходе АКФ 16 - числа случайных выбросов и их суммарной длительности в единицу времени.The indicated choice of the statistical parameter is due to the fact that the spontaneous emission of ACF 16 within the diffraction angle of reception, brought to the input of the ACF, is characterized by a very low level, corresponding to the presence in the noise optical signal of no more than one noise photon (quantum) per time

corresponding to the ACF intrinsic time constant. Moreover, the presence of even one external quantum (photon) of radiation at the input of ACF 16 causes a significant change in the statistical parameters (characteristics) of random (spontaneous) radiation at the output of ACF 16, namely: an increase in the number of random emissions of the amplitude of optical radiation per unit time, an increase in the total duration random emissions of the amplitude of the optical radiation per unit time. To detect individual quanta (photons) of the received optical signal supplied to the input of the ACF 16, the statistical parameters of the optical radiation at the output of the ACF 16 are measured - the number of random emissions and their total duration per unit time.

The release of a random process (signal) is an event that consists in the current implementation of a random process exceeding a given level of U _p . The duration of the ejection is the duration of a single exceeding of a threshold level by a random process.

n = 1, 2....; f_о - полоса квантового усиления АКФ 16. Длительность Δt_п определяет единицу времени (промежуток), в пределах которого осуществляют определение числа выбросов, а амплитуда U_п1 стробирующего импульса задает пороговый уровень U_п1, превышение которого случайным процессом X(t) и характеризуется как выброс амплитуды случайного процесса.Each of the cells 44 measures the statistical parameters of the signals from the outputs of the partial photosensitive elements of the MFP 22 corresponding to this cell. Cell 44 measures the number of random amplitude spikes, as well as the total duration of the random spikes of the optical radiation amplitude per unit time. Figure 3 shows a block diagram of one cell 44 determining the parameters of emissions. The input of the cell 44 is connected to one of the outputs of the MFP 22. The signal x (t) from the output of one of the partial photosensitive elements of the MFP 22 is fed to the input of the amplitude selector 55. At the same time, the input of the amplitude selector 55 receives a strobe pulse U _p1 from the output of the first clock generator 45 (pos. .45 in FIG. 2). This measurement process is then repeated periodically with the repetition rate of the strobe pulses coming from the sync generator 45. The duration of this strobe pulse U _p1 , equal to Δt _p , is determined by the first sync generator 45 (its parameters) and is chosen equal to the time interval equal to or a multiple of the ACF proper time constant Δt _n = n • Δt ₀ ,

n = 1, 2 ....; f _о is the quantum gain band of the ACF 16. The duration Δt _p determines the unit of time (interval) within which the number of emissions is determined, and the amplitude U _{p1 of the} gating pulse sets the threshold level U _p1 , the excess of which by a random process X (t) and is characterized as emission of the amplitude of a random process.

The sync generator 45 is a standard generator of periodically repeating rectangular pulses (gating pulses), the duration of which Δt _p is determined by the control signal (digital) coming from the information processing unit 28, in which, in accordance with the program, the value Δt _p = n • Δt ₀ is selected that is, the value of the number n, which determines the specified multiplicity Δt _{p the} value of the proper time constant of the ACF Δt ₀ . At the same time, the control register in block 45, by the signal received from block 28, determines the duration Δt _{p of} rectangular pulses generated by block 45. Similarly, the signals from block 28 carry out the establishment of the amplitude U _{p1 of} these pulses and the repetition frequency, which can be selected quite high. The nature of the processes in the cell for determining the parameters of emissions 44 is shown in figure 4. Figure 4 (a) shows the operation of the amplitude selector 55, where the following signals are indicated:
X (t) - input random signal (process) from the output of one of the partial photosensitive elements of the MFP 22; U _p1 - the amplitude of the strobe pulse from the output of the first sync generator 45 with a duration Δt _p ; X _a is the signal at the output of the amplitude selector 55, which is the outlier of the random process X (t), that is, part of the random process X (t), the amplitude of which exceeded a predetermined threshold level U _p1 (t is the time coordinate). Shaper 56 converts the output X _a at the output of the amplitude selector 55 into a rectangular pulse X _p with a corresponding duration τ _i equal to the duration of the ejection X _a , as shown in Fig. 4 (b). The first counter 57 counts the number N _{1 of the} generated pulses X _p for a given period of time Δt _p , which is determined by the first clock generator 45. For this, the signal U _p1 received by the amplitude selector 55 from the output of the first clock generator 45 is simultaneously transmitted to the second input of the counter 57 and determines the time interval Δt _p during which the number N _{1 of the} pulse-emissions X _p is calculated. At the same time, the formed rectangular pulse X _p from the output of the shaper 56 is fed to the gating stage 59, the second input of which receives a continuous sequence of short counting pulses C _i generated by the counter pulse generator 60. As a result, the rectangular pulse X _{p is} filled at the output of the gating stage with short counting pulses C _i , as shown in FIG. 4 (c). The signal X _{in is} fed to the input of the second counter 58, which calculates the number N _{2 of} counting pulses arriving at its input for a given period of time Δt _p . The value of the number of pulses N ₂ measured by the second counter 58 determines the total duration of the emissions of T _in a given period (unit) of time Δt _p . The total duration of the emissions is determined by the formula T _in = N ₂ • t _sch (10), where t _sch is the repetition period of the counting pulses generated by the counting pulse generator 60, which is known with a high degree of accuracy. To form a time interval for counting pulses N _{2, the} signal U _p1 from the output of the first clock generator 45 is also fed to the second input of counter 58.

Thus, as a result of the operation of the cell for determining the parameters of the emissions 44 at its outputs A and B periodically with the repetition rate of the strobe pulses U _p1 , signals are generated proportional to the number N _{1 of the} emissions of the amplitude of the random process (signal) X (t) entering the input of the cell 44 ( output A), and the number N ₂ proportional to the total duration of the emissions of the random process X (t) for a given period (unit) of time Δt _p . The signals at the outputs of cell 44 can be represented both in digital and in analog form, depending on the design parameters of the counters 57, 58. Subsequently, the signals at outputs A and B of cell 44 are denoted by S _A (t) and S _B (t), this implies any form of signal representation (digital or analog), which in the further presentation can be accepted by anyone and therefore not specified.

The signals S _A (t) and S _B (t) formed at the outputs of cell 44 are the statistical parameters (characteristics) of the random process X (t) from the output of some photosensitive partial element MFP 22, and ultimately characterize the random process of spontaneous emission from the output of the ACF 16 in one of the partial angles of reception of optical radiation.

где N_фп ²= N_фп•N_фп - число ячеек 44, равное числу парциальных фоточувствительных элементов в МФП 22.The considered determination of the parameters of the emissions of the random process X (t) in one cell for determining the parameters of the emissions 44 is carried out simultaneously and in parallel in all other cells 44 in figure 2. As a result, at the outputs of individual cells 44, signals are generated that characterize the statistical parameter (S _A or S _B ) of optical radiation at a working wavelength λ _slave in each individual partial spatial reception angle at the output of ACF 16. In the absence of an external optical signal at the input of ACF 16 measured statistical parameters S _a (t) and S _B (t) are functions of the time constant (average) since the parameters of spontaneous emission at the output of the ACF 16 are generally the same, fixed and equal to the average tdelnyh different partial reception angles. If there is an optical external signal at the input of ACF 16 in the corresponding partial reception angle at the output of ACF 16, the statistical parameters S _A (t) and S _B (t) undergo a change with respect to their average value. This result (effect) is used to detect the presence of an external signal at the input of the ACF 16 in one of the partial angles of reception of optical radiation. The signals S _A (t) and S _B (t) from the outputs of the counters 57 and 58 are fed to the inputs of the switch 58a, which is controlled from the information processing unit 28, to which the control input of the switch 58a is connected. Depending on the selected type of the measured statistical parameter S _A (number of emissions) or S _B (total duration of emissions), the switch 58a is set to “1” or “2” by command from the information processing unit 28 (see FIG. 3). In accordance with the established position of the switch 58a, in the future, when implementing the operations of the method, any particular selected type of statistical parameter (S _A or S _B ) is used. Determine the average value of the measured statistical parameter (S _A or S _B ) for all partial reception angles at the output of the ACF 16. For this, the signals from the outputs of the cells 44 (see figure 2) are simultaneously fed to the input of the first switch 46, which is sequentially in the polling mode connects the output of each cell 44 to the adder 47. Control and synchronization of the first switch 46 is carried out according to the signals received at this switch from the output of the information processing unit 28. The adder 47 performs the summation of signals S _A (t) (or S _B (t)) with sun outs ex cells 44 and forms the total value

where N _fp ² = N _fp • N _fp - the number of cells 44, equal to the number of partial photosensitive elements in the MFP 22.

Информация о средней величине S_o статистического параметра поступает с выхода ячейки 48 на вторые входы ячеек вычитания 49. На первые входы ячеек вычитания 49 поступают сигналы S_A(t) с выходов соответствующих ячеек определения параметров выбросов 44. Число ячеек 44 и ячеек 49 одинаково. В результате операций вычитания, производимых в ячейках вычитания 49, на их выходах образуются сигналы S_p, пропорциональные текущему отклонению статистического параметра S_A(t) от средней величины данного параметра S_o
S_p=S_A(t)-S_o (13)
Этим реализуется операция определения величины отклонения статистического параметра S_А от средней величины данного параметра (по ансамблю) для каждого из парциальных углов приема оптического излучения на выходе АКФ.(The processing of the signal S _A (t) from the output of the cells 44 is further considered. The processing of the signals S _B (t) is carried out in a similar manner). From the output of the adder 47, the signal S _{Σ is} fed to the input of the division cell 48, in which the operation of division by the value of N _fp ² (or multiplication by 1 / N _fp ² ) is carried out, as a result of which the value of S _o equal to the average value is formed at the output of the cell 48 measured statistical parameter S _A for all partial reception angles at the output of ACF 16

Information about the average value S _{o of the} statistical parameter comes from the output of cell 48 to the second inputs of the subtraction cells 49. The signals S _A (t) from the outputs of the corresponding cells for determining the emission parameters 44 are received at the first inputs of the cells of subtraction 49. The number of cells 44 and cells 49 is the same. As a result of the subtraction operations performed in the subtraction cells 49, signals S _p are generated at their outputs proportional to the current deviation of the statistical parameter S _A (t) from the average value of this parameter S _o
S _p = S _A (t) -S _o (13)
This implements the operation of determining the deviation of the statistical parameter S _A from the average value of this parameter (over the ensemble) for each of the partial angles of reception of optical radiation at the output of the ACF.

As a result, at the outputs of the cells 49 corresponding to the outputs of the statistical parameter determination unit, a time deviation function F (t) is formed equal to the difference between the current values of the statistical parameter S _A (t) and the average value of the statistical parameter S _о for each of the partial spatial angles of reception of optical radiation at ACF output 16
F (t) = S _A (t) -S _o . (14)
Next, the resulting set of signals F (t) is processed through two separate parallel channels.

 The first processing channel consists of a summing unit 25 and a first threshold block 26.

 The second processing channel consists of a correlation processing unit 24 and a second threshold unit 27.

 The signals from the output of the unit for determining statistical parameters 23 simultaneously and in parallel are supplied to the inputs of the summing unit 25 and the correlation processing unit 24.

Using the summing unit 25, the current time summation of the values of the deviation function F (t) is performed over a time interval T _c equal to the duration T _{a of the} optical signal analogous to the received radiation. The summing unit 25 performs the indicated operation as follows. The block diagram of the summing unit 25 is shown in figure 2. The summing unit 25 contains the summing cells 50, each of which is connected to the corresponding output of the statistical parameter determination unit 23. At the same time, the second control inputs of the summing cells 50 receive a control signal from the output of the second clock generator 52, which determines the operation of the cells 50 in the mode of summing the signals received at their inputs F (t). The duration of the control signal T _c determines the period of time summation T _c = T _a equal to the duration T _a signal-analogue of the received radiation.

Суммарный сигнал Z₁ представляет собой сумму значений функции отклонения F(t) в течение интервала времени суммирования Т_c, равного длительности сигнала-аналога принимаемого излучения. На выходе каждой отдельной (парциальной) ячейки суммирования 50 полученная сумма Z₁ определяет суммарное отклонение статистического параметра оптического излучения с выхода АКФ 16 от его среднего значения в соответствующем парциальном угле приема излучения на выходе АКФ 16.The second sync generator 52 periodically generates control signals (pulses of duration T _c ), ensuring the operation of each of the cells of the summation 50 in the mode of summing the output signal functions of the deviation F (t) from the outputs of block 23 within a time interval of duration T _c = T _a . As a result, the outputs of each of the cells of the summation 50 after exposure to a control signal of duration T _c produces a total signal Z _{1 of the} following form:

The total signal Z ₁ represents the sum of the values of the deviation function F (t) during the interval of the summing time T _c equal to the duration of the signal-analogue of the received radiation. At the output of each individual (partial) summing cell 50, the obtained sum Z ₁ determines the total deviation of the statistical parameter of optical radiation from the output of ACF 16 from its average value in the corresponding partial angle of radiation reception at the output of ACF 16.

Next, using the second switch 51 and the control signal from the output of the information processing unit 28 to the switch 51, each of the outputs of the summing cells 50 is connected in turn to the first threshold block 26, which compares the value of the sum Z ₁ (15) with the previously specified first threshold level P ₁ . When the sum Z ₁ exceeds the specified first threshold level P ₁ : Z ₁ > P ₁ , the output of the first threshold block 26 receives a corresponding signal that there is a threshold exceeded at the output of some i-th summation cell 50. The first and second threshold blocks 26 and 27 contain a comparison cell (switch) and a memory register in which a value of a predetermined threshold level P ₁ or P _{2 is} registered. If the condition Z ₁ > P ₁ (or Z ₂ > P ₂ ) is fulfilled, the comparison cell generates an impulse signal indicating that the specified threshold is exceeded, which enters block 28. In this case, the number of this i-th cell 50 is also determined in the information processing block 28 on based on what summing cell 50 at this point the switch 51 is connected to the input of a first threshold unit 26 in accordance with a control signal supplied to the switch 51 from the output of the information processing unit 28. When there are multiple summing cells 50, in which the sum of the value Z ₁ next predetermined strength threshold level P ₁ in the first threshold unit 26, information about the summation those cells 50 and their number corresponding to the partial photosensitive elements in the MFP 22 from the output unit 26 in the information processing unit 28 and recorded therein. When registering the excess of a predetermined threshold level in one of the cells of the summation 50 in the information processing unit 28, the number of this cell is recorded, and the fact of detection of the observed object (moment of detection) is recorded. In this case, the time t ₁ at which the object detection result is determined by exceeding the predetermined threshold is used to fix the coordinate of the detected object’s distance by the delay time between the time of radiation (formation) of laser radiation in the laser source 1 and time t ₁ , fixed when exceeding a predetermined threshold in one of the cells 50. The operation of determining the delay time is carried out in the information processing unit 28 using its own built-in Aymeri (current time counter).

In this case, for the moment of emission of the laser signal, the source of laser radiation is taken, for example, the moment of supply of the control signal from the output of block 28 to the source of laser radiation 1 or the moment of registration by the photodetector 38 of the optical signal arriving at it from the output of the source of laser radiation 1. The signal from the output of FP 38 through the unit for determining the duration 39 enters the input of the side 28. Simultaneously and in parallel, they process the signal-function deviations F (t) in the block of correlation processing 24. The block diagram of the block of correlation second processing 24 is shown in Figure 2. Block 24 contains correlators 53, the number of which corresponds to the number of subtraction cells 49 in the block for determining statistical parameters 23, and a third switch 54, the output of which is connected to the input of the second threshold block 27. The inputs of the correlators 53 are connected to the corresponding outputs of the subtraction cells 49 - outputs of the statistical determination block parameters 23. The second inputs of the correlators 53 receive, in the form of an electrical signal, an electrical signal analogous to the received radiation E _AE (t) previously stored in the memory unit 40. Each of the correlators 53 implements the formation of the inter-correlation function K (t) between the signal analog of the received radiation E _AE (t) and the deviation function F (t) generated at one of the outputs of the unit for determining statistical parameters 23, at one of the outputs of the corresponding subtraction cell 49 , the output of which is connected to the input of this correlator 53
K (t) = ∫E _AE (t) • F (t + τ) dt (16).
In each of the correlators 53, the obtained value of the cross-correlation functions K (t) is stored in the corresponding register, which is part of this correlator.

что позволяет повысить точность определения координаты дальности на основе принятого от объекта слабого оптического сигнала. При этом указанное сравнение величин K(t) и Р₂ осуществляют периодически один раз в конце промежутка времени Т_а, соответствующего длительности сигнала-аналога принимаемого излучения. Момент времени для осуществления сравнения сигналов на выходах корреляторов 53 со вторым заданным пороговым уровнем Р₂ во втором пороговом блоке 27 определяется управляющим сигналом, поступающим на вход третьего коммутатора 54 с выхода блока обработки информации 28 и определяющим перевод данного коммутатора 54 в режим запроса уровней сигналов с выходов корреляторов 53. Период поступления данного управляющего сигнала равен длительности Т_а и определяется блоком обработки информации 28.Next, the third switch 54 on the control signal from the output of the information processing unit 28, sequentially connects the outputs of the correlators 53 to the second threshold block 27. The second threshold block 27 sequentially compares the incoming values of the values of the cross-correlation function K (t) with the second predetermined threshold level P ₂ , and when K (t) exceeds the value of P ₂ at the output of any of the correlators
K (t)> P ₂ (17)
at the output of block 27, a signal is supplied to the information processing unit 28. As a result, information on the presence of one or more correlators 53 (and their numbers), the outputs of which the cross-correlation function K (t) exceeded the value of the specified second threshold level P ₂ (17). This information is recorded in the information processing unit 28 in the respective registers. At the same time, in the information processing unit 28, the time t _{2 of} exceeding the predetermined second threshold level is also recorded in one of the correlators 53. This time instant characterizes the coordinate of the range of the detected object and is determined in block 28 similarly to the time t ₁ for the summing unit 25, as discussed above . To determine the coordinate of the distance in time of the delay of the received signal from the object relative to the laser radiation signal emitted towards the object, either one of the time instants t ₁ , t ₂ , or the average between these instants of time is used

which allows to increase the accuracy of determining the coordinates of the range on the basis of a weak optical signal received from the object. Moreover, the specified comparison of the values of K (t) and P _{2 is} carried out periodically once at the end of the time interval T _a corresponding to the duration of the signal-analogue of the received radiation. The moment in time for comparing the signals at the outputs of the correlators 53 with the second predetermined threshold level P ₂ in the second threshold block 27 is determined by the control signal supplied to the input of the third switch 54 from the output of the information processing unit 28 and determining the transfer of this switch 54 to the mode of requesting signal levels from the outputs of the correlators 53. The period of receipt of this control signal is equal to the duration T _a and is determined by the information processing unit 28.

от его среднего ранее определенного значения S_o превышает заданный первый пороговый уровень P₁ за промежуток времени Т_а = Т_с, равный длительности сигнала-аналога принимаемого излучения.As a result, information processing unit 28 generates information about the presence (or absence) of a threshold P ₂ exceeded at the outputs of the correlators 53. As indicated, each individual output of the statistical parameter determination unit 23 corresponds to one partial angle of optical radiation reception at the output of ACF 16. As a result, the threshold processing performed by the first and second threshold blocks 26, 27 in the information processing unit 28, information is generated that characterizes the state of the statistical parameters of the optical radiation cheniya output ACF 16 in each of the partial spatial angles for the reception time interval T _{and the} corresponding duration T _c = T _a received analog signal radiation. Based on this generated information in the information processing unit 28, a decision is made about the presence of a detectable object in one of the partial spatial angles of reception of ω _p under the following conditions:
1. In one of the angles ω _{p the} total deviation of the statistical parameter

from its average previously determined value of S _o exceeds a predetermined first threshold level P ₁ for a period of time T _a = T _s equal to the duration of the signal analogue of the received radiation.

Z ₁ > P ₁ .

2. In one of the angles ω _p - the cross-correlation function K (t) exceeds the second predetermined threshold level P ₂ (17) over a period of time T _a = T _s .

3. Simultaneous fulfillment of the first or second conditions in several partial angles of reception ω _p1 , ω _p2 ... In this case, a decision is made on the presence of an extended object located in partial angles ω _p1 , ω _p2 ..., in which conditions 1 and 2, while the set of angles ω _p1 , ω _p2 ... characterizes the image of the detected object.

4. The simultaneous fulfillment of both conditions 1 and 2 in one or more reception angles ω _p1 , ω _p2 . In this case, a decision is made about the presence of an object in these reception angles ω _p1 , ω _p2 . Thus, if one of conditions 1, 2 is fulfilled separately or conditions 1 and 2 are fulfilled simultaneously in one or several partial reception angles ω _p , a decision is made on the presence (detection) of an object in those reception angles ω _p in which these conditions 1 and 2 simultaneously or separately performed. The simultaneous fulfillment of conditions 1 and 2 in the same angle of reception ω _p allows you to realize a higher probability of detecting an object. Recall that the absolute value of each of the partial solid reception angles, ω _p1 , ω _p2 , is equal to the diffraction reception angle ω _d , as previously established. Each of the reception angles ω _p1 , ω _p2 characterizes a certain angular coordinate of the observed field of view in which the object is detected. The information obtained in the processing unit 28 about the presence of an object in one or more receiving angles ω _d can be displayed, for example, on the display included in this unit.

 On this, the operations of laser location and detection of the observed object are completed.

 Formed in the information processing unit 28, information about the detection of the object, its coordinates corresponding to the angular coordinates of the partial elements of the FPM 22 photodetector, in which the threshold level of deviations of the statistical parameter is exceeded, as well as information about the coordinates of the distance of the detected object from the output of block 28 is sent to external information consumers (pos. . 43a in FIG. 1).

 Next, we consider the implementation of individual operations implemented by the device implementing the method. The operation of summing the current values of the deviation function F (t), performed in the cells of the summation 50 (figure 2), is implemented as follows.

A block diagram of one summing cell 50 is shown in FIG. The input of the summing cell 50 from the output of the subtraction cell 49 (see Fig. 2) continuously receives the implementation of the deviation function F (t). This signal F (t) is input to the annular switch 61 which has M outputs connected to the respective storage registers 62, whose number is also equal to M. The annular switch 61 sequentially connects the input time-IN _INPUT to the outputs _O in according to their sequence (exits) numbers: 1, 2, 3, ..., m. After reaching room exit m, annular switch 61 again connects its B input _Rin to the first output in _O numbered 1. Thus the circular carried cyclic connection input memory 62 to the input registers in _Rin connected to the output of the subtraction of the cell 49 (FIG. 2), that is, to the signal F (t) - the deviation function. At the time of connecting the memory register 62 to the input _I with the current value F (t), the corresponding memory register 62 registers the current value of the deviation function F (t) received at its input. Moreover, the previously registered value in this memory register 62 is erased. As a result, in the memory registers 62, a segment of the implementation of the deviation function F (t) is continuously recorded with time extent T _p = m • Δt ₁ , where m is the number of individual memory registers 62 included in the periodic recording of incoming information (ring); Δt ₁ - duration of the period of connection of the one memory register 62 to the input IN _INPUT connected to the corresponding output of the cell 49. The value of subtracting Δt ₁ can be represented as the period of registration values of the current implementation, the deflection function F (t). The duration Δt _{1 is} set equal to the unit of time for measuring the statistical parameter of optical radiation, which is respectively equal to one or more time constants t _{p of the} active quantum filter (ACF); t _p = 1 / f _o , where f _o is the quantum gain band of the ACF.

Установление величин m и Δt₁, определяющих работу кольцевого коммутатора 61, осуществляют с помощью схемы управления 65, по управляющим сигналам, поступающим на эту схему 65 с выхода блока обработки информации 28. В блоке обработки информации 28 значение величины Δt₁ - длительность единицы времени измерения статистического параметра - устанавливают заранее согласно априорному выбору режима измерения случайных сигналов на выходе АКФ. Данная величина Δt₁ выбирается равной Δt₁ = l•t_п, где l=1 или 2 и не подлежит в дальнейшем оперативному изменению. Величину m в блоке обработки информации 28 определяют на основании соотношения

где Т_с - ранее определенная в блоке 39 величина длительности сигнала-аналога принимаемого излучения. Информация о величине Т_с с выхода блока 39 поступила ранее после ее определения в блок обработки информации 28. Информация о величине Δt₁ и величине m с выхода блока обработки информации 28 поступает на схему управления 65 в цифровой форме по отдельному каналу связи. Следует отметить, что данная информация параллельно поступает на все ячейки суммирования 50 на содержащиеся в этих ячейках схемы управления 65. Схема 65 представляет собой цифровой специализированный дешифратор сигналов управления, поступающих с блока обработки информации 28. По поступившей закодированной информации о параметрах m и Δt₁ схема управления 65 вырабатывает сигнал, определяющий номер m выхода В_вых в кольцевом коммутаторе 61, после которого коммутатор 61 осуществляет вновь подключение первого выхода В_вых к своему входу В_вх.Thus, Δt ₁ = l • t _p ; l is 1; 2 .. The value of T _{p is} chosen equal to the duration of the signal analogue of the received radiation T _p = T _a . The value m of the number of involved memory registers 62 is thus determined by the duration T _{a of the} signal-analog of the received radiation, which was previously determined

The values of m and Δt ₁ determining the operation of the ring switch 61 are established using the control circuit 65, by the control signals supplied to this circuit 65 from the output of the information processing unit 28. In the information processing unit 28, the value of Δt ₁ is the duration of the measurement time unit statistical parameter - set in advance according to the a priori choice of the measurement mode of random signals at the output of the ACF. This value Δt ₁ is chosen equal to Δt ₁ = l • t _p , where l = 1 or 2 and is not subject to further operational change. The value of m in the information processing unit 28 is determined based on the ratio

where T _with - previously determined in block 39, the duration of the signal-analogue of the received radiation. Information about the value of T _s from the output of block 39 was received earlier after its determination in the information processing unit 28. Information about the value Δt ₁ and the value of m from the output of the information processing unit 28 is supplied to the control circuit 65 in digital form via a separate communication channel. It should be noted that this information is simultaneously sent to all summation cells 50 to the control circuits 65 contained in these cells. Scheme 65 is a digital specialized decoder of control signals received from the information processing unit 28. Based on the received encoded information about the parameters m and Δt _{1, the} circuit control 65 generates a signal which determines the number of m outputs _O in the annular switch 61, after which the switch 61 again performs the first output connection in _O to its entry in the _Rin.

Сформированная сумма Z₁ с выхода выходного сумматора 64 поступает далее на один из входов второго коммутатора 51, фиг.2, а через последний на вход первого порогового блока 26 при осуществлении считывания сигналов-сумм Z₁ с выходов ячеек памяти 50 в соответствии с ранее рассмотренной работой блока суммирования 25 (см. фиг.2).At the same time, the control circuit 65, in accordance with the value of the parameter Δt _1, generates a second control signal that determines the duration of the switching period Δt _{1 of} the outputs in the ring switch 61. To do this, in the last one, for example, switches some capacitance, the value of which determines the period (frequency) of switching the outputs in switch 61. The outputs of the ring switch 61 are connected to the inputs of the memory registers 62. By the signal-pulse from the output of the second clock generator 52 of figure 2, the output switch 63 performs fast serial connection of each memory register 62 to the input of the output adder 64. The latter performs the summation of all values of the quantities F (t) recorded at that moment of the supply of the control signal by the sync generator 52 in the memory registers 62. As a result, a value equal to the sum of all values is generated in the output adder 64 deviation function F (t) for a time T _p = T _s equal to the duration of the signal analogue of the received radiation

The generated sum Z ₁ from the output of the output adder 64 goes further to one of the inputs of the second switch 51, Fig. 2, and through the last to the input of the first threshold block 26 when reading the sum signals Z ₁ from the outputs of the memory cells 50 in accordance with the previously considered the operation of the summing unit 25 (see figure 2).

Thus, the summing cells 50 operate according to a sliding summation scheme of the deviation signal functions F (t) arriving at their inputs. Upon receipt of the input of cell 50 of a new value (reference) of the summation function F (t) within the elementary duration Δt _1, this new value F (t) is recorded in place of the very first value F (t) (the oldest) in the series of m registers 62, which is erased from the memory of this register 62.

Moreover, in the memory of the registers 62, the current values of the deviation function F (t) for the elapsed time period equal to T _p , which forms a "sliding window" in time, moving around the current implementation of the deviation function F (t) are constantly located. At any time, it is possible to read and sum information in the memory registers 62 for further threshold processing in the first threshold block 26 in order to determine if the deviation of the statistical parameter from its average value exceeds the current time interval T _p specified by the control signals from the information processing block 28 This reading operation is performed by the output switch 63 and the second switch 51 according to the signals from the output of the clock generator 52. The clock generator 52 generates periodic control vlyayuschie pulses, whereby a lump performed fast connection (serial) output register 62 to the adder 64. The frequency of arrival of these control pulses is determined, in turn, the control signal output to the timing generator 52 from the information processing unit 28.

Consider the implementation of correlation operations in the block of correlation processing 24, the block diagram of which is shown in figure 2. (see pos. 24). The correlation processing unit 24 contains correlators 53, each of which is connected to the output of the corresponding elementary partial channel of the statistical parameter determination unit 23. The second inputs of the correlators are connected to the output of the memory unit 40. The outputs of the correlators 53 are connected to the third switch 54. Each of the correlators 53 performs the formation of a cross-correlation function between the current values of the deviation function F (t) arriving at their first and second inputs in one of the partial reception angles ω _p optical radiation and a signal analogue of the received radiation. Figure 6 shows the block diagram of the first embodiment of the correlator 53. The number of correlators 53 is equal to the number of outputs of block 23 and, accordingly, the number of partial photosensitive elements in the MFP 22. Elements pos. 66 - 69 are identical to the elements of the same name pos. 61 - 63; 65 in the summation cell 50, the operation of which is discussed above. These elements in the correlator 53 perform the same function as in cell 50, namely, they isolate the current values of the deviation function F (t) within the time interval T _a equal to the duration of the signal of the analogue of the received radiation, that is, elements of pos. 66 to 68; 69 form a “sliding window” in time, moving along the current implementation of the deviation function F (t).

ПФ 79 выделяет (пропускает) в одном из первых боковых порядков дифракции сигнал К (t) и задерживает любые другие фоновые (помеховые) сигналы, которые могут возникнуть в плоскости ПФ 79. Фотоприемник 80 осуществляет считывание сигнала К(t) и направляет его в блок промежуточной памяти 82 (буферный регистр), откуда данный сигнал направляют в третий коммутатор 54 фиг.2 и далее во второй пороговый блок 27 для выполнения операции сравнения со вторым заданным пороговым уровнем.The signal of the deviation function F (t) from the output of the output switch 68 (see Fig. 6) is fed to the input of the intermediate frequency generator 70, and from its output to the acousto-optic modulator 71. The output switch 68 by the control signal received from the output of the processing unit information 28, performs a serial connection memory register 67 to the input of the intermediate frequency generator 70 (IF), whereby at the input of the generator 70 is formed consistent implementation deflection function F (t) within _a time interval t equal to the duration ti radiation received analog signal. This implementation F (t) was previously registered in the memory registers 67 and is continuously updated (progressing in time) as the ring switch 66 operates. The acousto-optic light modulator 71 converts the intermediate frequency electrical signal from the output of the IF generator 70 to the spatial modulation of the light flux created by the source the light 72 and the beam expander 73. The IF 70 includes an amplitude modulator that amplitude modulates the intermediate frequency signal, generating st IF generator 70 in accordance with the deviation signal function F (t), coming to the input of inverter generator 70. As a result, the control input of the acoustooptic light modulator 71 (AOM) receives an intermediate frequency signal, the modulated signal deflection function F (t). The piezoelectric transducer 83, which is part of AOM 71, converts this signal into a traveling acoustic wave in a transparent medium for light AOM 71, made, for example, of quartz. The luminous flux from the light source 72 after passing through the AOM 71 acquires spatial phase modulation corresponding to the deviation function F (t). For small indices, the phase modulation is equivalent to the amplitude modulation of the light beam. Thus, the AOM 71 carries out the input of the signal F (t) into the optical system (Fig.6), performing the operation of forming a cross-correlation function. The first lens 74 forms in the plane of the first spatial filter 75 the Fourier spectrum of the signal F (t). The spatial filter 75 selects (passes) the spectrum of the signal F (t), which is localized in one of the first diffraction orders corresponding to the spatial frequency determined by the intermediate frequency from the IF generator 70. The zero diffraction order is blocked by the filter 75. The second lens 76 performs the inverse Fourier transform and forms in the plane of the transparent light-modulating screen 84 of the light-modulating CRT 77 (SELT) a filtered image of the signal F (t), which due to the movement in time of the acoustic wave in A M 71 also continuously moves relative spatial signal recorded on a light-modulating screen 84. SELT 77 performs the function of the reference mask. On the light modulating screen 84, a spatial distribution E (x) is recorded corresponding to a signal analog of the received radiation E _AE (t), previously registered in the memory block pos. 40 in FIG. 1. The recording of the signal E _AE (t) on the light modulating screen 84 is as follows. The signal E _AE (t) from the memory unit 40 is supplied in analogue electrical form via an electronic amplifier 81 to the control electrode of an electronic searchlight 85 SELT 77, which, by electron scanning and modulating the electron beam in intensity, applies an electric charge E to the light modulating screen 84 (SE) x), with a distribution proportional to the signal E _AE (t). SE 84 is made of an electro-optical crystal and carries out spatial modulation of the transmitted light flux in accordance with the applied charging relief E (x) corresponding to the analog signal E _AE (t). To accomplish this, the SC 84 is placed between two crossed polarizers 86, 87, which convert the light modulation into polarization, which produces the SC 84 made of an electro-optical crystal, into the amplitude modulation of the light flux, under the influence of the charge relief E (x) deposited on it by the electron beam. As a result, at the optical output of SELT 77, that is, at the input of the third lens 78, a spatial optical signal is generated proportional to the product E _AE (t) • F (t + τ), in which the component F (t + τ) moves relative to the signal E _AE (t). The third lens 78 integrates the generated work over space and generates in the plane of the second spatial filter (PF) 79 a signal proportional to the cross-correlation function K (t)

PF 79 selects (passes) in one of the first lateral diffraction orders the signal K (t) and delays any other background (interference) signals that may occur in the plane of PF 79. The photodetector 80 reads the signal K (t) and sends it to the block intermediate memory 82 (buffer register), from where this signal is sent to the third switch 54 of figure 2 and then to the second threshold block 27 to perform the comparison operation with the second predetermined threshold level.

Thus, in the considered correlator 53 (block diagram in FIG. 6), the cross-correlation function K (t) is directly formed within the duration of the analog signal T _a , while the mutual movement of the analyzed signal - F (t) is the deviation function and the reference fixed mask - E (x) - proportional to the signal analogue of the received radiation E _AE (t) is carried out by moving the acoustic wave in the AOM 71.

 The considered correlator 53, made on the basis of optical information processing, has high speed and accuracy of complex integrated operations.

 The main element of the correlation analysis unit 24, the correlator 53, can be performed entirely on digital elements in a compact design. Next, we consider such a correlator 53, which implements the formation of the cross-correlation function K (t) in digital form, made on the basis of fast Fourier transform (FFT) processors - the second variant of the construction of the correlator 53. Figure 7 shows a block diagram of a second variant of the correlator 53.

и комплексно-сопряженный Фурье-спектр Ф $\genfrac{}{}{0ex}{}{\text{*}}{\text{A}}$ (ω), который регистрируют в регистре памяти эталона 99.

оператор преобразования Фурье.Elements pos. 91 - 94 are identical to the elements of the same name pos. 61 - 63; 65 in the summing cell 50. From the output of the output switch 93, the input of the first processor of the FFT 95 receives the signal of the deviation function F (t) with a time duration T _a equal to the duration of the signal-analogue of the received radiation. The input of the second processor FFT 96 from the memory unit 40 receives a signal analogue of the received radiation E _AE (t). The FFT processor 96 digitally forms the Fourier spectrum Ф _A (ω) of the analog signal

and complex conjugate Fourier spectrum $\genfrac{}{}{0ex}{}{\text{*}}{\text{A}}$ (ω), which is recorded in the memory register of the reference 99.

Fourier transform operator.

функции отклонения F(t). Перемножитель 98 осуществляет формирование произведения S_A(ω)•Ф $\genfrac{}{}{0ex}{}{\text{*}}{\text{A}}$ (ω), которое далее подвергают Фурье-преобразованию (обратному) в третьем процессоре БПФ 97, на выходе которого в результате формируют функцию взаимной корреляции сигналов F(t) и Е_АЭ(t) в соответствии с известным соотношением между функцией корреляции и произведением Фурье-спектров

где К (t) - функция взаимной корреляции.First FFT processor 95 generates Fourier spectrum

deviation function F (t). The multiplier 98 implements the formation of the product S _A (ω) • Ф $\genfrac{}{}{0ex}{}{\text{*}}{\text{A}}$ (ω), which is then subjected to the Fourier transform (inverse) in the third FFT processor 97, at the output of which, as a result, a cross-correlation function of the signals F (t) and E _AE (t) is formed in accordance with the known relationship between the correlation function and the Fourier product -spectra

where K (t) is the cross-correlation function.

 The advantage of the implementation of the correlator 53 based on digital FFT processors and processor-multiplier 98 is the ability to create small-sized equipment.

 Functionally, the correlators 53 based on optical information processing processors (first embodiment of FIG. 6) and FFT digital information processing processors (second embodiment of FIG. 7) are identical.

 Consider the operation of the formation of threshold levels.

The formation of the values of the first and second predetermined threshold P ₁ , P ₂ levels is as follows (see figure 1).

The generated optical signal-analogue of the received radiation E _A (t) is directed to the input of the ACF 16. For this, the first reflective mirror 14 is set to position P ₂ by the movement unit 15 by the control signal from the information processing unit 28. In this state, the input of the ACF 16 an optical signal is received that is analogous to the received radiation, branched off from the optical output of the first forming lens 33 by means of a second translucent mirror 37 and directed by reflective mirrors 30a, 31. The second forming lens 34 implements the parallel light flux coming further to the input of the ACF 16. Then, with the optical signal-analogue of the received radiation, all the same operations are performed as the operations for receiving radiation reflected from the observed object, discussed above. The difference lies in the fact that the analog signal E _A (t) is received in one of the partial angles of reception of optical radiation at the output of the ACF 16, and at this receiving angle, which corresponds to the analog signal E _A (t), and threshold parameters are determined levels P ₁ and P ₂ .

Perform spectral selection and amplification of the signal analogue of the received radiation E _A (t) in ACF 16 at a working wavelength λ _slave . In each of the partial spatial angles of reception of ω _p at the output of the ACF 16, a statistical parameter of optical radiation at the working wavelength is determined by means of the statistical parameter determination unit pos.23 in the same way as described above when performing operations to detect optical signals reflected from the object. As a statistical parameter, one of the previously considered parameters is used, for example, the number of random outliers. In block 23, the average value of the statistical parameter of the optical radiation at the output of the ACF 16 is determined for all partial spatial angles of reception at the output of the ACF 16, similar to that described above. In one of the partial reception angles at the output of the ACF 16, corresponding to the angular direction of the optical signal analogous to the received radiation E _A (t) received at the input of the ACF 16, the current time deviation of the statistical parameter of optical radiation from the measured average value of this statistical parameter is determined as a function time and form the deviation function F ₂ (1) equal to the difference of the current values S (t) of the statistical parameter and its average value S _o
F ₂ (t) = S (t) -S _about (20).

The formation of this deviation F ₂ (t) is carried out in the partial angle of reception of the signal-analogue of the received radiation, corresponding, for example, to the center line of the ACF 16, and using the partial elementary photosensitive element in the MFP 22 located in the center of the MFP 22 on the axis O-O ' in the focus of the concave mirror 18, since the diaphragm 35 forming the light beam is also located in the center on the optical axis of the optical system of the forming lenses 33, 34, as shown for example in figure 1. Moreover, this central photosensitive element in MFP 22 corresponds to the partial angle of reception of the optical signal-analogue of the received radiation at the output of the ACF 16. The value of the deviation function F ₂ (t) for the signal-analogue of the received radiation is generated at the output of the statistical parameter determination unit 23. Moreover, in as a statistical parameter can be used, as was discussed above, the number of random emissions of the amplitude of optical radiation per unit time over an arbitrarily chosen fixed ur vnem or total duration of random amplitude optical emission radiation in a unit time over an arbitrarily selected fixed level.

Полученная величина Z₂ поступает с выхода блока суммирования 25 в блок 41, где регистрируется в регистре памяти этого блока. Далее по сигналу управления с выхода блока обработки информации 28 блок измерения первого порогового уровня 41 передает значение величины Z₂ из своего регистра памяти в первый пороговый блок 26, в котором величина Z₂ регистрируется в регистре, определяющем величину первого порогового уровня P₁ = Z₂. Этим осуществляется установление первого заданного порогового уровня P₁. Формирование второго порогового уровня P₂ осуществляют с помощью блока корреляционной обработки 24 и второго блока измерения порогового уровня 42. В блоке корреляционной обработки 24 осуществляют формирование взаимно корреляционной функции К₂(t) между запомненным электрическим сигналом-аналогом принимаемого излучения Е_АЭ(t) и сформированной функцией отклонения F₂(t) на интервале времени Т_c, равном длительности сигнала-аналога Е_А(t) также для центрального канала обработки информации с выхода блока 23. С выхода БКА 24 сигнал l(t), соответствующий текущим значениям функции взаимной корреляции К₂(t), поступает на вход второго блока измерения порогового уровня 42

Второй блок измерения порогового уровня 42 представляет собой регистратор максимального уровня поступающего на его вход сигнала. Для этого он содержит регистр памяти и ячейку сравнения (компаратор). Первый поступающий в блок 42 сигнал регистрируется в его регистр памяти. Последующие сигналы подвергаются сравнению в ячейке сравнения с ранее зарегистрированным сигналом в регистре, при этом в дальнейшем в регистр записывается наибольший сигнал. В результате к концу времени обработки Т_а в регистре памяти блока 42 будет зарегистрирована величина, соответствующая максимальному из сигналов, поступивших на вход блока 42, то есть максимальное значение функции взаимной корреляции К₂
M₂ = max{K₂(t)} = max{∫F₂(t)E(t-τ)dt} (23)
Данную величину М₂ принимают за второй заданный пороговый уровень Р₂ = М₂. Аналогично блоку 41 в блоке измерения второго порогового уровня 42 сигнал М₂ из регистра памяти блока 42 по команде от блока обработки информации 28 поступает на второй пороговый блок 27, где регистрируется в регистре, определяющем величину второго заданного порогового уровня Р₂ = М₂. В результате рассмотренных операций в первом и втором пороговых блоках 26, 27 устанавливают величины первого и второго заданных пороговых уровней P₁, Р₂. Установленные пороговые уровни соответствуют выходным сигналам блока определения статистических параметров 23, образующимся при поступлении на вход АКФ 16 оптического сигнала-аналога принимаемого излучения Е_А(t), сформированного на основе данных о предполагаемой дальности до объекта, а также априорных данных о параметрах объекта и трассы распространения излучения. Это позволяет осуществить прием и обнаружение оптических сигналов, отраженных от объекта, с параметрами, в среднем соответствующими априорно установленным при формировании сигнала-аналога параметрам эталонного (предполагаемого) объекта в пределах предполагаемой дальности до объекта.Further, in the summing unit 25 and in the correlation processing unit 24, the generated deviation function F ₂ (t) is simultaneously processed to determine the first and second threshold levels P ₁ , P ₂ , respectively. In this case, the processing is carried out only in one central channel corresponding to the photosensitive element in the MFP 22, which also corresponds to the partial angle of reception of the optical signal-analogue of the received radiation. The formation of the first threshold level P _{1 is} carried out using the summing unit 25 and the first measurement unit of the threshold level 41, which contains a memory register, the write and read control of which is carried out by commands from the information processing unit 28 to which the block 41 is connected. In the summing unit 25, the current values of the deviation function F ₂ (t) are summed over a time interval T _c equal to the duration of the previously generated analog signal of the received radiation T _a for the central information processing channel from the output of the statistical parameter determination unit 23. The resulting sum Z _{2 is} received for the value of the first predetermined threshold level P ₁ :

The obtained value of Z ₂ comes from the output of the summing unit 25 to block 41, where it is registered in the memory register of this block. Further, according to the control signal from the output of the information processing unit 28, the measurement unit of the first threshold level 41 transfers the value of Z ₂ from its memory register to the first threshold block 26, in which Z _{2 is} registered in the register that determines the value of the first threshold level P ₁ = Z ₂ . This sets the first predetermined threshold level P ₁ . The formation of the second threshold level P _{2 is} carried out using the correlation processing unit 24 and the second threshold level measurement unit 42. In the correlation processing unit 24, a mutually correlation function K ₂ (t) is generated between the stored electrical signal analogous to the received radiation E _AE (t) and formed deviation function F ₂ (t) in the time interval t _c, equal duration analog signal E _a (t) and for the center channel output from the information processing unit 23. The output 24 BCA signal l (t), the corresponding conductive current values of the cross-correlation function R ₂ (t), is input to the second threshold level measurement unit 42

The second block for measuring the threshold level 42 is a registrar of the maximum level of the signal arriving at its input. For this, it contains a memory register and a comparison cell (comparator). The first signal arriving at block 42 is recorded in its memory register. Subsequent signals are compared in a comparison cell with a previously registered signal in the register, with the largest signal being subsequently recorded in the register. By the end of the processing time T _a memory block in the register 42 is registered value corresponding to the maximum of the signals received at the input of block 42, i.e. the maximum value of the cross-correlation function R ₂
M ₂ = max {K ₂ (t)} = max {∫F ₂ (t) E (t-τ) dt} (23)
This value M _{2 is} taken as the second predetermined threshold level P ₂ = M ₂ . Like block 41 in the block for measuring the second threshold level 42, the signal M ₂ from the memory register of block 42 is sent to the second threshold block 27 by a command from the information processing unit 28, where it is registered in the register determining the value of the second predetermined threshold level P ₂ = M ₂ . As a result of the operations considered in the first and second threshold blocks 26, 27, the values of the first and second predetermined threshold levels P ₁ , P _{2 are set} . The established threshold levels correspond to the output signals of the unit for determining statistical parameters 23, which are formed when the optical signal analogous to the received radiation E _A (t), which is generated on the basis of data on the estimated distance to the object, as well as a priori data on the parameters of the object and the path, is received at the ACF 16 input. radiation propagation. This allows the reception and detection of optical signals reflected from the object, with parameters, on average, corresponding to the a priori set when forming the analog signal parameters of the reference (estimated) object within the estimated range to the object.

 After the formation of threshold levels, the first reflective mirror 14 with the help of the displacement block 15 is set to position P1, at which optical signals from the output of the receiving telescope 12, 13 are received at the input of the ACF 16.

Consider the operation of the unit for measuring duration 39. The unit for measuring duration 39 performs the operation of measuring the duration of the generated signal-analogue of the received radiation, which is input to the unit 39 in electrical form from the output of the recording photodetector 38. A block diagram of the unit for measuring duration is shown in Fig. 9. The input signal of the measuring unit of duration 39, the signal analogue of the received radiation E _A (t) is shown schematically in Fig. 8 (b) and represents the sum of several short (elementary) pulses of short duration τ ₂ , forming some total pulse with a total duration of T _a , the measurement of which is carried out by block 39. The principle of operation of block 39 is similar to the principle of operation of the above-described cell for determining the emission parameters of items 44 in Figures 1, 3, and 4. In this case, cell 44 measures the duration of rectangular pulses (Corresponding to the emissions) and measures the duration of the intervals between pulses. The duration measuring unit 39 measures the total total duration T _a in Fig. 8 (b), for which, in block 39, both the duration of the rectangular pulses from the output of the first shaper 102 are measured (see Fig. 9), and the measurement of the durations of the intervals between pulses on Fig (b), as a result of which, when summing the obtained values in the adder 100, the total total duration T _{a is formed} .

The amplitude selector 101 and the first driver 102 operate similarly to blocks 55, 56 in FIG. 3 and form rectangular pulses corresponding to elementary pulses τ ₂ in the analog signal in FIG. 8 (b). The gate stage 103 and the first counter 84 are similar to the corresponding elements in the cell 44 in FIG. 3 carry out the calculation (measurement) of the total duration of the generated rectangular pulses. To determine the gaps between the pulses generated in the first shaper 102, an inverter 106 is introduced, which converts the polarity of the signals to the opposite. As a result, a sequence of pulses arrives at the input of the second shaper 107, the positive emissions of which correspond to the gaps between the initial pulses at the output of the first shaper 102. The second shaper 107 includes a differentiating cell, which distinguishes the boundaries of the generated pulses, and the generation circuit itself, which generates rectangular pulses from signals with the output of this differentiating cell, corresponding to the position of the intervals between pulses at the output of the first driver 102. Next Torah gate stage 108 and second counter 109 perform measurement of the total duration of rectangular pulses generated.

The resulting value enters the adder 100 and is summed with the value measured by the elements 102, 103, 104. As a result, the output of the adder 90 forms a signal (in digital form) corresponding to the total duration T _a of the analog signal received radiation in Fig. 8 (b ) The measured value T _a from the output of the adder 100 then goes to the information processing unit 28 in figure 1.

 Laser location device that implements the proposed method of laser location, made on the basis of standard blocks and nodes.

 As a laser radiation source 1, for example, a photodissociation laser with an active substance in the gas phase based on perfluoroalkyl iodides and pumped using powerful pulsed optical radiation sources is used. The active laser element 2 in this case is made in the form of a cell with a working substance in the gas phase. The active quantum filter 16 is a low-noise quantum amplifier, which can also be implemented, for example, on the basis of a photodissociation laser with the indicated active substance and pumped using pulsed optical radiation sources.

As the information processing unit 28, a standard PC with interface units for receiving and transmitting pulse control signals is used. The software of block 28 (PC) includes a sequence of operations for switching on and starting up individual blocks of a location-based device, as well as calculating and determining the parameters of the attenuation filter β ₀ in the block of attenuation of radiation, as well as setting time intervals for measuring signals in the blocks for measuring statistical parameters and correlation analysis. Computing operations in block 28 (PC) are carried out using a special computing processor. The PC - block 28 - also includes an information display unit (display), operator input and control devices, archive and random access memory blocks.

 The interchangeable filter unit 36 is, for example, an optical-mechanical unit with interchangeable calibrated optical filters that are moved using a stepper motor.

 The first reflective mirror 14 is provided with a movement unit 15, for example, based on a stepper motor, which allows the mirror 14 to be brought out of the optical radiation passage after measuring operations. The laser radiation modulation unit 5 is an electro-optical crystal, for example, based on potassium dihydrogen phosphate, located between the crossed polarizers 6 and 7. When a modulating signal arrives at the electro-optical crystal 5 from the modulating generator 8, the crystal 5 modulates the transmitted light radiation in phase, which is crossed by polarizers 6 and 7 is converted to amplitude modulation, as a result of which the laser radiation generated by the laser radiation source 1 becomes moduli ovannym time amplitude in accordance with the modulating signal. As the modulating generator 8, for example, a rectangular pulse train generator or a sinusoidal signal generator is used. Modulation of laser radiation by a pseudo-noise signal is possible. In this case, an electronic pseudo noise signal generator is used as the modulating generator 8. To modulate laser radiation with linear frequency modulation (LFM) pulses, an electronic generator of LFM pulses is used as generator 8.

 The use of various types of modulating signals and the corresponding generators 8 can improve the tactical and technical characteristics of the location device in the specific conditions of its application. As the modulation unit 5, it is possible to use an acousto-optic crystal (modulator), which provides modulation in time of the losses inside the resonator of the laser radiation source 1.

 The light-modulating CRT 77 contains a light-modulating screen 84 made of an electro-optical crystal, for example, potassium dihydrogen phosphate, and can be constructed in its structure, for example, similarly to the SELT considered and described in [10], [11].

 The unit for determining statistical parameters, the units of summation, correlation analysis, threshold and measuring units are made on the basis of standard digital or analog elements, which are pulse signal generators based on triggers, multivibrators, electronic meters, electronic controlled threshold devices, electronic switches, switches, and gating and inverting circuits. The memory blocks and memory registers are made on the basis of standard memory cells, which provide registration, memorization and controlled non-destructive reading of memorized analog or digital signals. These elements are used in modern pulse technology and can be implemented based on the above principle of operation of each of the blocks. Fast Fourier Transform (FFT) processors 95, 96, multiplier 98 are specialized digital processors with a program focused on performing only Fourier transform or multiply signals in digital form. To perform these operations, it is also possible to use standard high-performance PCs.

 To convert the control signals into analog or digital form when the executive units are coupled with the information processing unit 28 or with each other, standard analog-to-digital (or DAC) converters are included in the corresponding blocks or elements.

 Let us consider in more detail the implementation of the proposed method of laser location using a laser location device. In this method, the detection of the optical signal reflected from the observed object is carried out by analyzing and continuously determining the statistical parameters of optical radiation at the output of ACF 16, the input of which comes from the output of the receiving telescope, radiation from the observed region of space. Active quantum filter 16 provides high sensitivity of the laser location device when receiving optical signals reflected from the object.

где f_o - полоса квантового усиления АКФ в единицах частоты

f₀ ~ 300 МГц, Δt₀ = 3•10^-9с. При этом согласно теоретическим и экспериментальным исследованиям [9] величина минимально обнаружимого входного оптического сигнала равна

время корреляции шумов на выходе АК,
П_э - полоса усиления электронного усилителя, входящего в состав МФП 22,
Δν - ширина линии усиления АКФ в

,
С - скорость света,
ω_п,ω_д - пространственные (телесные) углы приема ω_п и дифракционный угол АКФ.Feature ACF 16 is that sufficiently large gain K _at> 1000 a system consisting of the ACF 16 and the MFP 22 own MFP 22, the noises cease to play any significant role, and the sensitivity of the system only depends on the characteristics of the ACF 16 and approaching to the ultimate quantum sensitivity, determined by the ability to detect and register one quantum of external optical radiation entering the input of the ACF 16 in the quantum gain band Δν at a working wavelength λ _slave . In this case, the level of intrinsic spontaneous noise of the ACF 16 reduced to the input of the ACF, which determines the ultimate quantum sensitivity of the ACF, is characterized by the presence on average of one noise photon at the input of the ACF in the reception angle ω _p corresponding to the diffraction angle ω _d and for the time interval Δt ₀ corresponding to size

where f _o is the quantum gain band of the ACF in frequency units

f ₀ ~ 300 MHz, Δt ₀ = 3 • 10 ^-9 s. Moreover, according to theoretical and experimental studies [9], the value of the minimum detectable input optical signal is

time correlation of noise at the output of the AK,
P _e - gain band of the electronic amplifier, which is part of the MFP 22,
Δν - ACF gain line width in

,
C is the speed of light
ω _p , ω _d - spatial (solid) reception angles ω _p and the diffraction angle of the ACF.

 The high sensitivity of ACF 16 is directly related to the statistical parameters (characteristics) of spontaneous emission at the output of the ACF.

коэффициент корреляции,
α = 4π•f $\genfrac{}{}{0ex}{}{\text{2}}{\text{Э}}$ ; f_э - эквивалентная энергетическая ширина спектра случайного процесса, которая несколько превышает полосу f₀ квантового усиления АКФ 16 f_Э = a₁•f₀ (a₁ = 1,2 при коэффициенте усиления АКФ К_у ~ 10³ - 10⁴).The spontaneous emission at the output of ACF 16 at one partial receiving angle ω _p , which is a random noise signal, can be approximated approximately and represented as a normal stationary random process with a correlation function
K _n (τ) = σ ² R (τ),
where σ ² is the variance of the random process,

correlation coefficient,
α = 4π • f $\genfrac{}{}{0ex}{}{\text{2}}{\text{E}}$ ; f _e - equivalent energy width of the spectrum of a random process, which is somewhat higher than f ₀ band quantum amplification ACF 16 f _{e 1} = a • f ₀ (a ₁ = 1.2 at a gain K ACF _y ~ March ¹⁰ - April ^10).

где m - среднее значение.For such a random process, the number of emissions per unit time N ₁ (C) above the threshold level C can be determined as follows [12]:

where m is the average value.

при τ = 0.
Для промежутка времени Δt₀, на котором осуществляют измерение числа выбросов, среднее число выбросов N_cp = Δt₀•N₁(C). Измерение числа выбросов N_ср осуществляют в течение промежутка времени Δt₀, равного или кратного постоянной времени АКФ t_п, обратно пропорциональной величине fo полосы квантового усиления АКФ

n=1, 2, 3,....

at τ = 0.
For the time interval Δt ₀ , which measure the number of emissions, the average number of emissions N _cp = Δt ₀ • N ₁ (C). The measurement of the number of emissions N _{sr is} carried out over a period of time Δt ₀ equal to or a multiple of the time constant of the ACF t _p inversely proportional to the value fo of the quantum gain band of the ACF

n = 1, 2, 3, ....

Для выбранной аппроксимации случайного процесса, с учетом

для нулевого среднего значения m = 0, получаем величину N_cp

где С - уровень отсчета амплитуды выброса.From here we obtain an estimate of the number of emissions of a random process (spontaneous emission) at the output of ACF 16 per unit of measurement time Δt ₀ :

For the selected approximation of a random process, taking into account

for zero mean value m = 0, we obtain the value of N _cp

where C is the reference level of the amplitude of the ejection.

(n = 1, 2, 3).For the threshold level, C = 0.1 • σ; a ₁ ~ 1.2,
N _cp = 0.96 • n (29),
where n is a number determined from the condition for choosing a unit of time for measurement

(n = 1, 2, 3).

The obtained relation for N _cf shows that within the time constant of ACF 16 t _p (for n = 1) a random signal at the output of ACF 16 has no more than one outlier above the threshold level C = 0.1σ. This single emission contains at least 75% of the energy of the entire noise signal over time t _p . In accordance with formula (24) and, as shown in [9], within the time interval t _p = 1 / f _{о, the} energy of fluctuation noise brought to the input of ACF 16 in the partial diffraction reception angle does not exceed the energy of one photon (quantum) per working wavelength λ _slave Based on the estimate obtained for the average number of outliers N _cp, this allows us to conclude that a single outlier of a random signal at the ACF output within the time interval t _p = 1 / f _о corresponds to an equivalent noise photon at the input of ACF 16 in the partial diffraction reception angle ω _n . Therefore, the calculation of the number of emissions N of a random optical signal at the output of the ACF 16 corresponds to the calculation of the number of equivalent noise photons at the input of the ACF for the corresponding period of time. The average number of emissions N _cp , measured over the entire ensemble of partial elementary reception angles of ω _p radiation at the output of ACF 16, is a very accurately measurable quantity having a very small intrinsic dispersion (scatter) due to the stationarity of a random signal within small measurement durations corresponding to several time constants t _p , t _o = nt _p , and also due to the presence of a very large number of elementary spontaneous emitters - excited atoms in the working substance of ACF 16.

Thus, when choosing the time interval for measuring the statistical parameters of radiation at the output of ACF 16 equal to one or more time constants t _p ACF: t _o = nt _p , n = 1, 2, 3, we obtain an accurate and stable value of the statistical parameter (emission of a random signal ) corresponding to an average of one photon noise equivalent time t for _n = 1 / f _of one partial diffraction angle ACF receiving inlet 16. in this case, the presence of inlet 16 ACF one external photon optical signal reflected from an object, results in substantially y change the statistical parameter (number of emissions or the total emission time) that can be reliably detected with a high probability, close to 100%. Indeed, the presence within a given time interval of measuring t _о instead of one pulse (ejection) of two pulses or instead of three pulses of four pulses, i.e., one pulse (photon) more, is an easily feasible task of detecting one external photon from the received optical signal and is implemented with almost 100% probability of correct detection. The probability of false alarm here is almost zero due to work in the photon counting mode at the quantum limit of sensitivity. Indeed, as shown above and in [9], the presence of one equivalent noise photon at the ACF input within the time constant t _p corresponds to a certain average power of spontaneous radiation at the ACF output in the diffraction reception angle and the appearance of another noise photon in the same time interval and in the same diffraction angle would mean a 2-fold increase in this average spontaneous emission power, which is an incredible event.

Based on the foregoing, it can be argued that the choice of unit time t _o measuring the statistical parameter of radiation at the output of ACF 16 within one or more time constants of the ACF t _p = 1 / f _о allows you to realize the ultimate quantum sensitivity of a device that implements the method and ensure the registration of individual external photons with a high probability of correct detection with zero probability of false detection (false alarm). The specified detection of external single-photon optical signals is carried out within a given period of time T _a >> t _p equal to the duration of the previously generated signal-analogue of the received radiation. As a result of this, the proposed method implements the ultimate quantum sensitivity not only when receiving optical signals with a short pulse duration corresponding to the ACF time constant t _p = 1 / f _о (which was implemented in [9]), but also when receiving optical signals with an arbitrarily large duration t _imp >> t _p , significantly exceeding the time constant of the ACF t _p .

Indeed, in the process of analyzing the statistical parameters of optical radiation at the output of the ACF 16 during the duration T _{and the} signal-analogue of the received radiation, they continuously calculate the number of random process emissions (or emission durations) at individual elementary time intervals Δt _and equal to (or multiple with a small amount ) time constant t _p ACF 16. In this case, the measured number of emissions is compared with the ensemble average for a given elementary time interval Δt _and , which Paradise has been measured previously and is fairly stable and well defined. The deviation from this average value, due to the appearance of one external photon (quantum) at the input of ACF 16 during an elementary time interval Δt _{, is} detected with a high degree of probability, and the process of detecting one external photon is implemented over the entire long period of time T _a , which can significantly actually exceed the elementary time interval Δt, _and determines its own time constant t _f ACF 16. This is because during large compared with t _p = t _o = 1 / f _of the interval in Yemeni corresponding analog signal duration T _and is carried in the magnitude of the summation of deviations of the statistical parameter from its average value over the ensemble for a small period of time n • t _n (n = 1, 2, 3), but not the total number of random emissions. As a result, the appearance of an external radiation quantum is detected, and not lost in the total number of random emissions, as occurs with direct integration of the signal from the ACF output over a long period of time. As a result, it is possible to detect single-photon signals reflected from the object by using a laser radiation illuminating the object with a long duration, which corresponds to a long duration T _{a of} an analog signal of the received radiation. This is an advantage of the proposed method and LLR in comparison with the prototype [9], which implements the detection of single-photon signals and the ultimate quantum sensitivity for a short period of time t _о , corresponding to the time constant t _о = 1 / f _о ACF 16. As a result of using for illumination object of laser radiation with a long duration of the emitted pulse T _imp >> t _o realized a higher potential and range of the laser location device that implements the proposed method.

To increase the likelihood of detecting optical signals reflected from the object, use is made of the time modulation of the generated laser radiation by means of the laser radiation modulation unit pos. 5 in FIG. 1. At the same time, some initial regularity is introduced into the generated laser radiation used to illuminate the object, which can be detected by receiving an optical laser signal reflected from the object, and which makes the object more likely to be detected compared to receiving only a single-photon signal from the object. Fig. 8 (a) is a schematic representation of an oscillogram of a generated and modulated laser pulse for illuminating an object. The time coordinate is plotted along the abscissa, and the normalized signal amplitude E (laser intensity) is plotted along the ordinate. The laser radiation formed by the laser generator 1 is a pulse of long duration T _imp , consisting of several elementary pulses of shorter duration τ ₁ . This form of laser radiation was obtained using 8 rectangular pulse generator as a modulating generator. It is possible to use other forms of modulation of laser radiation, for example, a sinusoidal signal using the appropriate generator of modulating sinusoidal signals. As a result of propagation along an extended path to a distance L and reflection from the object, the laser radiation E undergoes significant attenuation and undergoes changes that can lead to a significant or complete loss of the original waveform of the laser radiation E (t). In this case, the radiation received from the object at the input of the receiving telescope 12 may be one or more photons located in places on the time scale corresponding to the location in the original laser radiation E _and FIG. 8 (a) elementary pulses with a duration of τ ₁ . In the intervals between elementary pulses, individual photons in the received radiation will obviously be absent. On Fig (b) schematically shows the waveform analogue of the received radiation corresponding to the generated and modulated laser radiation in Fig. 8 (a). An analog signal of the received radiation generated according to this proposed method based on modulated laser radiation used to illuminate the object is a model signal that, on average, corresponds to the expected optical signal from the object at the input of the receiving telescope 12. The waveform is the analog of the received radiation ( figb) corresponds to the shape of the expected signal from the object and may differ significantly from the shape of the original modulated laser radiation E _and Fig.8 ( a). Individual elementary pulses of duration τ ₁ in the original laser radiation in the analog signal E _a may have a shorter duration τ ₂ or be completely absent, and may also have a different (non-rectangular) distribution, as shown in Fig. 8 (b). The total duration of the signal analogue of the received radiation T _a may be less than the duration T _{imp of the} initial laser pulse, due to a significant attenuation of radiation during propagation along the path. At the same time, an analog signal of the received radiation is formed on the basis of specific a priori information about the expected object, the distance to the object and attenuation of radiation in the atmosphere. As a result, the shape of the generated signal-analogue of the received radiation E _A reflects the possible shape of the real received signal from the object at the input of the receiving telescope 12 in the presence of the object at the estimated range L (or closer). This allows you to use the generated signal-analogue of the received radiation E a _as a reference signal when detecting an optical signal reflected from the object. In this proposed method, the generated signal-analogue of the received radiation is used as a reference for the correlation processing of optical radiation from the output of the ACF 16. This further improves the probability of detecting an object by determining the correlation between deviations from the average statistical parameters (emissions) in the radiation at the output of the ACF 16 and the shape of the (temporary) generated signal analogous to the received radiation E _a . Indeed, as shown above, individual emissions in the radiation at the output of the ACF 16, exceeding the average values of the statistical parameter, characterize the presence of external photons at the input of the ACF 16 at the corresponding time points, which correspond to the presence in the analog signal E _A in Fig. 8 (b) individual elementary bursts of amplitude, of duration τ ₂ within the duration of T _{a of} the received signal analogue signal itself. As a result, between the analog signal E _A (t) and the deviation function F (t) from the average statistical parameter in the time interval T _a, there is some correlation, which is determined using the correlation processing of radiation at the output of ACF 16.

Detection of an object in this method is carried out simultaneously both on the basis of correlation processing and on the basis of determining the total values of the deviation function for the duration of the duration Ta of an analog signal of the received radiation. This makes it possible to realize a higher detection probability at long ranges to the object L, since at a long range L, a significant attenuation of the signal from the object is possible, in which the shape of the received radiation is completely lost, and the radiation at the input of the receiving telescope 12 is a single-photon pulse, corresponding to one of elementary pulses τ ₂ in the signal-analogue on figb. In this case, detection based only on correlation processing is impossible, however, the summing unit will detect and register a single-photon signal. When receiving from the object a more intense reflected signal, both processing channels pos. 24 and 25 simultaneously register and detect the presence of a signal from the object. Thus, the presence of two parallel information processing channels from the output of the statistical parameter determination unit 23 — the correlation processing unit 24 and the summing unit 25 — makes it possible to increase the probability of detecting an object. The decision on the presence of an object is made upon receipt of a signal exceeding a predetermined threshold level, at least in one of the blocks 24 or 25, or while exceeding the threshold levels in both blocks 24, 25. Setting the predetermined threshold levels P ₁ and P ₂ based on processing in blocks 24 and 25 of the signal-analogue of the received radiation can improve the reliability of detection of the object, since in this case the expected values of the object and the distance to the object are taken into account in the values of P ₁ and P ₂ .

 As noted, in the laser receiving device (LPC), created on the basis of the iodine near-infrared photodissociation quantum amplifier (ACF), it is possible to achieve an extremely high quantum sensitivity and register single-photon pulsed signals. The practical application of this facility in laser ranging and communication systems will be determined by its noise immunity in relation to various background radiation and interference. The operation of laser communication and location systems in the atmosphere is always carried out against the background of radiation from natural formations (earth's surface, cloud fields), which create background noise and reduce the range of laser location systems (LLS).

 It is known that the range of the visible and near infrared ranges in the daytime is significantly less than the range when working at night. This is due to the fact that, for example, in pulsed location systems, the threshold sensitivity of the system is largely determined by the number of background photons per pulse duration of the received signal. In this regard, it is of interest to assess the influence of external background noise on the threshold sensitivity of a healthcare facility based on iodine photodissociation ACF operating in the regime of ultimate quantum sensitivity. The active medium in ACF consists of excited iodine atoms I *, which are formed as a result of photodissociation of the initial working substance under the influence of optical pumping.

Следует также отметить, что фильтрация принимаемого оптического сигнала в АКФ осуществляется не в результате его ослабления вне пределов полосы пропускания, как это происходит в пассивных оптических фильтрах, а в результате усиления сигнала в пределах полосы квантового усиления Δν $\genfrac{}{}{0ex}{}{\text{c}}{\text{1/2}}$ .
Оптическое излучение вне пределов полосы усиления Δν $\genfrac{}{}{0ex}{}{\text{c}}{\text{1/2}}$ свободно проходит через АКФ и непосредственно воздействует на фотоприемник (МФП) в виде фоновой помехи. Для ослабления этой фоновой помехи, прошедшей через АКФ, используется пассивный оптический фильтр, расположенный в любом месте между выходом АКФ и МФП. Полоса пропускания этого фильтра Δν_f должна быть по возможности минимальной.A feature of photodissociation ACF is a very narrow spectral band of quantum gain, which at half maximum in the optimal operating mode is

It should also be noted that the filtering of the received optical signal in the ACF is carried out not as a result of its attenuation outside the passband, as is the case with passive optical filters, but as a result of signal amplification within the quantum gain band Δν $\genfrac{}{}{0ex}{}{\text{c}}{}$$\genfrac{}{}{0ex}{}{}{\text{1/2}}$ .
Optical radiation outside the gain band Δν $\genfrac{}{}{0ex}{}{\text{c}}{}$$\genfrac{}{}{0ex}{}{}{\text{1/2}}$ freely passes through the ACF and directly affects the photodetector (MFP) in the form of background noise. To attenuate this background noise passing through the ACF, a passive optical filter is used located anywhere between the output of the ACF and the MFP. The passband of this filter Δν _f should be as minimal as possible.

As a passive optical filter, interference filters can be used, which are the narrowest of the passive filters used. However, the bandwidth of modern interference filters Δν _f is several orders of magnitude greater than the quantum gain band Δν $\genfrac{}{}{0ex}{}{\text{c}}{}$$\genfrac{}{}{0ex}{}{}{\text{1/2}}$ ACF.

 As will be shown below, with a sufficiently high gain of the ACF, the background that does not fall into the amplification band of the ACF will practically not affect the sensitivity of the healthcare facility. Therefore, the sensitivity of the healthcare facility will be determined only by the ratio between the spectral density of the brightness of the background source and the spectral density of the brightness of zero vacuum oscillations. Therefore, even against the background of the solar disk, the sensitivity of this healthcare facility will be only 12% worse than when working at night.

 To filter the external background radiation entering through the ACF to the MFP input, a passive narrow-band optical filter is used (hereinafter simply a passive filter).

The central wavelength of the passive filter λ _f coincides with the working wavelength λ _{0 of the} ACF corresponding to the center of its gain band.

где I $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω,Ω}}$ - спектральная плотность яркости нулевых колебаний вакуума, K⁽⁺⁾(ω) - коэффициент усиления АКФ на частоте ω,ω≥0. Здесь учтено, что в пределах контура усиления Δν $\genfrac{}{}{0ex}{}{\text{c}}{\text{1/2}}$ в АКФ происходит усиление излучения фоновой помехи в K⁽⁺⁾(ω) раз. Вне пределов контура усиления АКФ фоновое излучение беспрепятственно проходит на вход МФП, ослабляясь только в пассивном фильтре. Представим (30) в виде

В такой записи в первом слагаемом в прямоугольных скобках фоновое излучение как бы уравнивается в правах с квантовым шумом, приведенным ко входу усилителя. Отличие фонового излучения от квантового шума учитывается вторым слагаемым, которое описывает фоновое излучение как прошедшее через АКФ без усиления.Consider the work of hospitals in the mode of external background illumination. Suppose that in addition to the useful signal, the input of the ACF receives background radiation that is constant in time and uniformly fills the entire input aperture of the healthcare facility (diameter of the input input aperture d _a , area S _a ). We will characterize one of its polarizations by the spectral density of energy brightness I $\genfrac{}{}{0ex}{}{\text{phn}}{\text{ω, Ω}}$ . Then the spectral density of the energy brightness of the radiation of one of the polarizations transmitted through the ACF and passive filter with transmission T _f (ω)

where i $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω, Ω}}$ is the spectral density of the brightness of zero vacuum oscillations, K ⁽⁺⁾ (ω) is the amplification factor of the ACF at the frequency ω, ω≥0. Here, it is taken into account that within the gain loop Δν $\genfrac{}{}{0ex}{}{\text{c}}{}$$\genfrac{}{}{0ex}{}{}{\text{1/2}}$ In ACF, background noise radiation is amplified K ⁽⁺⁾ (ω) times. Outside the limits of the ACF gain loop, background radiation passes unhindered to the MFP input, attenuating only in the passive filter. We represent (30) in the form

In such a record, in the first term in rectangular brackets, the background radiation is as if equalized in rights with the quantum noise reduced to the input of the amplifier. The difference between the background radiation and quantum noise is taken into account by the second term, which describes the background radiation as transmitted through the ACF without amplification.

Спектральная плотность энергетической яркости, определенная для всех частот, как положительных, так и отрицательных
(I_ω,Ω)_out = I $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω,Ω}}$ K_Σ(ω), (35)
где

если ω≥0 и

если ω<0.
Телесный угол приема Ω_r, представляющий поле поле зрения одного элемента МФП, равен

где d_r - диаметр приемной площадки ФП; f_L - эквивалентный фокус оптической системы. Тогда спектральная плотность энергетической яркости излучения, прошедшего АКФ и пассивный фильтр, с учетом того, что на элемент МФП попадает только излучение, которое выходит из АКФ в телесном угле Ω_r

Корреляционная функция этого излучения

где

Ω_d = π(ϑ_d/2)² = π²λ $\genfrac{}{}{0ex}{}{\text{2}}{\text{0}}$ /16S_a -
телесный дифракционный угол, ϑ_d = λ/d_a - плоский дифракционный угол.For the convenience of further consideration, we rewrite (31) in the form
(I $\genfrac{}{}{0ex}{}{\text{(+)}}{\text{ω, Ω}}$ ) _out = I $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω, Ω}}$ K $\genfrac{}{}{0ex}{}{\text{(+)}}{\text{Σ}}$ (ω), (32)
where is the resulting gain
K $\genfrac{}{}{0ex}{}{\text{(+)}}{\text{Σ}}$ (ω) = [(K ⁽⁺⁾ (ω) -1) (1 + β) + β] • T _f (ω), (33)
a

Spectral density of energy brightness, determined for all frequencies, both positive and negative
(I _{ω, Ω} ) _out = I $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω, Ω}}$ K _Σ (ω), (35)
Where

if ω≥0 and

if ω <0.
The solid reception angle Ω _r representing the field of view of one MFP element is

where d _r is the diameter of the receiving pad FP; f _L is the equivalent focus of the optical system. Then the spectral density of the energy brightness of the radiation passing through the ACF and a passive filter, taking into account the fact that only radiation that leaves the ACF in the solid angle Ω _r, enters the MFP element

Correlation function of this radiation

Where

Ω _d = π (ϑ _d / 2) ² = π ² λ $\genfrac{}{}{0ex}{}{\text{2}}{\text{0}}$ / 16S _a -
solid diffraction angle, ϑ _d = λ / d _a - flat diffraction angle.

где

Δω $\genfrac{}{}{0ex}{}{\text{c}}{\text{ef}}$ = 2πcΔν $\genfrac{}{}{0ex}{}{\text{c}}{\text{ef}}$
(для гауссова контура)

Средняя по ансамблю мощность шумового излучения на выходе фильтра в предположении, что средняя интенсивность <I(r, t)> на выходе АКФ равномерна

Фототок элемента МФП пропорционален мощности падающего на него излучения, усредненной по интервалу времени, равному постоянной времени электронного усилителя τ_e

За время τ_e≤10 мкс случайное поле на выходе АКФ может рассматриваться как стационарное, поскольку время жизни инверсии существенно больше τ_e. Поэтому можем считать в силу эргодичности случайного процесса, что средняя мощность шумового излучения, падающего на элемент МФП

Среднее значение тока элемента МФП, отвечающее средней мощности шумового излучения Mi_nr, где

где М - коэффициент умножения элемента МФП, η - его квантовая эффективность;

чувствительность элемента (фотодиода), е - заряд электрона; ℏ - постоянная Планка; ω₀ - частота лазерного излучения; ℏω₀ - энергия кванта лазерного излучения на рабочей длине волны.Without violating the generality of further analysis, we assume that the value of T _f (ω) is constant throughout the passband of the passive filter. We approximate the spectral characteristic of the latter by the rectangular function rect (λ) with the transparency bandwidth Δλ _f and transmission at the maximum T _f . Outside of the band Δλ _{f, the} passivity of the passive filter is assumed to be zero. Then the ensemble average noise intensity at the filter output

Where

Δω $\genfrac{}{}{0ex}{}{\text{c}}{\text{ef}}$ = 2πcΔν $\genfrac{}{}{0ex}{}{\text{c}}{\text{ef}}$
(for gaussian contour)

The ensemble average noise power at the filter output under the assumption that the average intensity <I (r, t)> at the ACF output is uniform

The photocurrent of the MFP element is proportional to the power of the radiation incident on it, averaged over the time interval equal to the time constant of the electronic amplifier τ _e

For a time τ _e ≤ 10 μs, the random field at the output of the ACF can be considered stationary, since the inversion lifetime is much longer than τ _e . Therefore, due to the ergodicity of the random process, we can assume that the average power of the noise radiation incident on the MFP element

The average value of the current of the MFP element, corresponding to the average noise emission power Mi _nr , where

where M is the multiplication coefficient of the MFP element, η is its quantum efficiency;

the sensitivity of the element (photodiode), e is the electron charge; ℏ - Planck's constant; ω ₀ is the frequency of laser radiation; ℏω ₀ is the quantum energy of laser radiation at the working wavelength.

 Since the ACF operates in a subthreshold mode, the random field at its output, due to spontaneous emission, is Gaussian. The random background radiation field is also assumed to be Gaussian.

и со спектральной плотностью энергии, согласованной с контуром усиления АКФ
S_ω = E $\genfrac{}{}{0ex}{}{\text{ent}}{\text{s}}$ g_s(ω-ω_s), (43)
где E_s ^ent - энергия сигнала на входном зрачке ЛПУ, площадью S_a; g_s(ω-ω_s) - функция, описывающая форму спектра входного сигнала и полностью попадающая в контур усиления АКФ с шириной полосы Δν $\genfrac{}{}{0ex}{}{\text{c}}{\text{ef}}$ . Тогда, энергия сигнала на выходе АКФ
E_s ^out=E_s ^entK_s (44)
где

Будем считать, что центр картины Эйри, образованной плоской волной полезного сигнала в фокусе линзы совпадает с центром приемной площадки элемента МФП, представляющей собой круг диаметром d_r (случай, когда совпадения нет, требует отдельного рассмотрения). Тогда энергия полезного сигнала, попадающая на один элемент МФП, равна

где

функция Релея.Let the input of the ACF receive a useful received signal with the wave vector k _s , the angle between which and the optical axis of the ACF

and with a spectral energy density consistent with the ACF gain loop
S _ω = E $\genfrac{}{}{0ex}{}{\text{ent}}{\text{s}}$ g _s (ω-ω _s ), (43)
where E _s ^ent is the energy of the signal at the entrance pupil of the hospital, area S _a ; g _s (ω-ω _s ) is a function that describes the shape of the spectrum of the input signal and completely falls into the amplification circuit of the ACF with a bandwidth Δν $\genfrac{}{}{0ex}{}{\text{c}}{\text{ef}}$ . Then, the energy of the signal at the output of the ACF
E _s ^out = E _s ^ent K _s (44)
Where

We assume that the center of the Airy pattern formed by a plane wave of the useful signal at the focus of the lens coincides with the center of the receiving pad of the MFP element, which is a circle with a diameter of d _r (the case when there is no coincidence requires a separate consideration). Then the energy of the useful signal falling on one element of the MFP is equal to

Where

Rayleigh function.

где N_s - энергия полезного сигнала на входе АКФ, выраженная в числах фотонов. На выходе электронного усилителя, стоящего за МФП на эквивалентном сопротивлении нагрузки R получим напряжение полезного сигнала с амплитудой V_s ^max= K_eRМi_s ^max, где K_e - коэффициент усиления ЭУ на нижней границе его полосы усиления.If τ _e is equal to the pulse width of the useful signal at the output of the ACF, then the current surge corresponding to the energy of the useful signal incident on the MFP element

where N _s is the energy of the useful signal at the input of the ACF, expressed in numbers of photons. At the output of the electronic amplifier behind the MFP at the equivalent load resistance R, we obtain the voltage of the useful signal with amplitude V _s ^max = K _e RМi _s ^max , where K _e is the gain of the EU at the lower boundary of its gain band.

где i_dc - среднее значение темнового тока; F - коэффициент шума фотодиода; С - результирующая входная емкость; I_е ^*2 - спектральная плотность флуктуации тока эквивалентного токового источника шума усилителя; V_е ^*2 - спектральная плотность флуктуации напряжения эквивалентного шумового источника напряжения усилителя, П_e - полоса усиления электронного усилителя МФП.In the phase transition circuit, in addition to current fluctuations caused by the random nature of spontaneous and background radiation from the ACF output, there are also fluctuations due to the shot effect of the phase transition, thermal noise of the resistive elements, and the noise of the EI. Assuming the listed types of fluctuations are statistically independent, we can write that the output dispersion of the fluctuation

where i _dc is the average value of the dark current; F is the noise figure of the photodiode; C is the resulting input capacitance; I _e ^{* 2} is the spectral density of the fluctuation of the current of the equivalent current noise source of the amplifier; V _e ^{* 2} is the spectral density of voltage fluctuations of an equivalent noise amplifier voltage source; P _e is the gain band of an MFP electronic amplifier.

We will look for the minimum detectable input signal of the considered radiation detector by comparing the voltage caused by the signal at the output of the EI with the root mean square voltage fluctuation σ _V caused by noise. According to the Chebyshev inequality, P (| V- <V> | ≥mσ _V ) ≤m ^-2 . This means that the probability of a voltage deviation from the average value due to random fluctuations by an amount greater than or equal to mσ _V does not exceed m ^-2 . Therefore, a signal for which the signal-to-noise ratio is m will be recorded with a probability that is not less than 1 − m ⁻² .

(49)
где

квантовый предел чувствительности МФП прямого детектирования.Compare (V $\genfrac{}{}{0ex}{}{\text{max}}{\text{s}}$ ) ² cm ² σ $\genfrac{}{}{0ex}{}{\text{2}}{\text{V}}$ . From the equality (V $\genfrac{}{}{0ex}{}{\text{max}}{\text{s}}$ ) ² = m ² σ $\genfrac{}{}{0ex}{}{\text{2}}{\text{V}}$ we obtain the equation for N _min

(49)
Where

quantum limit of sensitivity of MFP direct detection.

The influence of fluctuation noise on the level of the minimum detectable signal is determined by β, i.e., by the ratio of the spectral density of the energy brightness of these noises to the spectral density of the energy brightness of zero vacuum oscillations, as well as the value of the gain of spontaneous emission <K _sp > in the ACF. This remark is important because it allows us to conclude that for some sufficiently large <K _sp > the influence of background noise, as well as the intrinsic noise of the MFP on the sensitivity of the healthcare facility can be made very small. We examine this issue in more detail.

Его решение

Если фона нет, то

При достаточно большом коэффициенте усиления <K_sp ²> второе слагаемое под корнем много больше единицы.If the condition <K _sp >>> П _f / П _ef ^c is fulfilled, then <K _sp ^c >>> П _f / П _ef ^c , where П _f is the passive filter band and П _ef ^с is the effective ACF gain band. Then, the contribution of noise caused by the non-amplified background can be neglected in comparison with the spontaneous emission and background amplified in the ACF. Let us estimate the ratio P _f / P _ef ^c for a passive filter with the following parameters: Δλ _f = 5 nm (P _f = 8.67 • 10 ¹¹ Hz); T _f = 0.5. Since the effective gain band of the ACF P $\genfrac{}{}{0ex}{}{\text{c}}{\text{ef}}$ = cΔv $\genfrac{}{}{0ex}{}{\text{c}}{\text{ef}}$ = 3.6 • 10 ⁸ Hz, then P _f / P _ef ^c ≅ 2400, and thus, in order to exclude the influence on the sensitivity of the healthcare facilities of the background that passed ACF without amplification, it is enough that <K _sp >> 3 • 10 ⁴ . As for the intrinsic noise of the MFP and the noise of the amplifier, they do not contribute to the fluctuations of the photocurrent even with the gain in the ACF, starting from the value of K _s = 3 • 10 ³ , that is, <K _sp > ≅0.35K _s ≅10 ³ .
As a result, for N _min we obtain the equation

His decision

If there is no background, then

For a sufficiently large gain <K _sp ² >, the second term under the root is much larger than unity.

(53)
характеризующее, во сколько раз ухудшается чувствительность при наличии фона, и задаться допустимым значением ε, то можно найти допустимое значение спектральной плотности энергетической яркости фона, отвечающее заданному ε. Для ЛПУ допустимое значение спектральной плотности яркости фона и задается формулой

где

Из этого выражения видно, что при достаточно большом <K_sp ²> произведение ξ_mK_s≫1 и β $\genfrac{}{}{0ex}{}{\text{АКФ}}{\text{per}}$ ≅ ε-1. (55) (55)
Мы видим, что при характерных параметрах ЛПУ с йодным АКФ допустимое значение фоновой засветки определяется только величиной ε. Если допустить при наличии фона ухудшение чувствительности ЛПУ в 2 раза, то допустимое значение спектральной плотности энергетической яркости фона будет равно спектральной плотности энергетической яркости нулевых колебаний вакуума
(I $\genfrac{}{}{0ex}{}{\text{phn}}{\text{ω,Ω}}$ ) $\genfrac{}{}{0ex}{}{\text{АКФ}}{\text{th}}$ = I $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω,Ω}}$ ,
что составляет для λ_раб = 1,315 мкм

Сравним полученные результаты с фоновой засветкой, производимой небом в дневное время I $\genfrac{}{}{0ex}{}{\text{dsk}}{\text{λ,Ω}}$ и солнечным диском I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{λ,Ω}}$ . Спектральная плотность энергетической яркости солнечного диска для одной из поляризаций

(56)
составляет примерно одну пятую часть I $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω,Ω}}$ :

Вблизи земной поверхности из-за влияния атмосферы эта величина еще меньше. Яркость солнечного диска на уровне земной поверхности составляет I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{ω,Ω}}$ = 3•10⁷Вт•м^-2мкм^-1•cp^-1 на λ = 0,5 мкм. Соответственно яркость неба днем составляет I $\genfrac{}{}{0ex}{}{\text{dsk}}{\text{λ,Ω}}$ = 10^-5I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{ω,Ω}}$ на λ = 0,5 мкм в максимуме спектра излучения.Determine the permissible exposure level of the healthcare facility, β $\genfrac{}{}{0ex}{}{\text{ACF}}{\text{per}}$ , from the allowable deterioration in the sensitivity of healthcare facilities compared with the sensitivity caused only by spontaneous radiation of ACF. If denoted by

(53)
characterizing how many times the sensitivity deteriorates in the presence of a background, and ask an acceptable value of ε, then you can find the acceptable value of the spectral density of the energy brightness of the background corresponding to a given ε. For healthcare facilities, the allowable value of the spectral density of the brightness of the background is given by the formula

Where

It can be seen from this expression that for sufficiently large <K _sp ² > the product ξ _m K _s ≫1 and β $\genfrac{}{}{0ex}{}{\text{ACF}}{\text{per}}$ ≅ ε-1. (55) (55)
We see that for the characteristic parameters of an IOD with iodine ACF, the admissible value of the background illumination is determined only by the value of ε. If, in the presence of a background, a 2-fold deterioration in the sensitivity of healthcare facilities is allowed, then the allowable value of the spectral density of the energy brightness of the background will be equal to the spectral density of the energy brightness of zero vacuum oscillations
(I $\genfrac{}{}{0ex}{}{\text{phn}}{\text{ω, Ω}}$ ) $\genfrac{}{}{0ex}{}{\text{ACF}}{\text{th}}$ = I $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω, Ω}}$ ,
which is for λ _slave = 1,315 μm

Compare the results with the background light produced by the sky in the daytime I $\genfrac{}{}{0ex}{}{\text{dsk}}{\text{λ, Ω}}$ and solar disk I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{λ, Ω}}$ . The spectral density of the energy brightness of the solar disk for one of the polarizations

(56)
makes up about one fifth of I $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω, Ω}}$ :

Near the earth's surface, due to the influence of the atmosphere, this value is even smaller. The brightness of the solar disk at ground level is I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{ω, Ω}}$ = 3 • 10 ⁷ W • m ^-2 μm ^-1 • cp ^-1 at λ = 0.5 μm. Accordingly, the brightness of the sky during the day is I $\genfrac{}{}{0ex}{}{\text{dsk}}{\text{λ, Ω}}$ = 10 ^-5 I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{ω, Ω}}$ at λ = 0.5 μm at the maximum of the radiation spectrum.

Следовательно, даже при работе на фоне солнечного диска чувствительность ухудшится только на 12%.To determine I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{ω, Ω}}$ and I $\genfrac{}{}{0ex}{}{\text{dsk}}{\text{λ, Ω}}$ at λ = 1.315 μm, one can use the spectral characteristic of solar radiation, according to which I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{ω, Ω}}$ (λ = 1.3) = 0.125 • I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{λ, Ω}}$ (λ = 0.5). It follows that I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{λ, Ω}}$ (λ = 1.315) = 0.375 • 10 ⁷ W • m ^-2 μm ^-1 suffering, and for one of the polarizations I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{λ, Ω}}$ (λ = 1.315) = 0.188 • 10 ⁷ W • m ^-2 μm ^-1 sp and is approximately one eighth of I $\genfrac{}{}{0ex}{}{\text{νac}}{\text{ω, Ω}}$ . Thus

Therefore, even when working against the background of the solar disk, the sensitivity worsens by only 12%.

Это является весьма полезным качеством данного рассматриваемого ЛПУ, так как позволяет не только эффективно без снижения дальности действия работать в дневных условиях, но позволяет также исключить срыв сопровождения объекта слежения при прохождении данным объектом области его траектории, расположенной по отношению к ЛПУ на фоне солнечного диска.Thus, the background illumination from the solar disk, and even more so from the daytime sky, is practically much less than the admissible background illumination and does not affect the sensitivity of healthcare facilities with iodine ACF. This facility with iodine ACF can work with the same limit level of quantum sensitivity both at night and in the daytime. This is due to the following factors: a very narrow band of quantum gain Δν $\genfrac{}{}{0ex}{}{\text{c}}{}$$\genfrac{}{}{0ex}{}{}{\text{1/2}}$ high ACF gain, reaching several thousand units, as well as the effect of suppressing the intrinsic noise of the MFP and external background noise that did not fall into the amplification band of the ACF. Moreover, as was shown, spontaneous ACF noises have the main effect on the sensitivity of HCIs with iodine ACF, and the intrinsic noises of the AF and external background noises are suppressed and their interfering effect decreases and tends to zero with increasing gain. Comparison (I $\genfrac{}{}{0ex}{}{\text{phn}}{\text{ω, Ω}}$ ) _per with the spectral density of the energy brightness of the solar disk I $\genfrac{}{}{0ex}{}{\text{sun}}{\text{ω, Ω}}$ at λ _slave = 1.315 μm indicates that the MPI based on iodine ACF has the ability to receive useful signals even against the background of the solar disk

This is a very useful quality of this medical facility under consideration, since it allows us not only to work effectively in daylight conditions without reducing the range, but also allows us to exclude the tracking object tracking failure when this object passes its trajectory located in relation to the medical facility against the background of the solar disk.

Let D ₀ - the range of the receiving device (PU) in the absence of interference, and D _p - in the presence of interference. If we introduce the parameter γ _p = D _p / D ₀ , which characterizes the decrease in the range of the PU in the presence of interference in comparison with the range in the absence of interference, then for medical facilities with iodine ACF, γ _{p is} close to its maximum value of unity, since the range , determined in the general case by the value of N _min , practically does not decrease during the operation of medical facilities with iodine ACF even under conditions of strong quasi-solar background noise. Based on this, it can be argued that this facility is a high noise immunity receiving device, for the disruption of which a very high-energy interference is needed, exceeding the brightness of the solar disk and falling into a very narrow band of quantum gain of the ACF.

 Experimental studies of an experimental sample of a device that implements the method confirmed the receipt of a higher probability of detecting weak optical signals reflected from the object. realizing the reception of optical signals with extremely high quantum sensitivity and single-photon optical signals when the object is illuminated by laser radiation with a long pulse duration and high total energy but limited radiation power, as well as an increase in the efficiency and range of the laser location system as a whole. The latter is achieved due to the simultaneous implementation of the ultimate single-photon quantum sensitivity and the reception and registration of laser radiation with a long pulse duration, which allows to increase the total energy of laser radiation to illuminate the object and, accordingly, increase the range of the laser location system using a laser transmitter - a laser radiation source - with limited radiation power achievable in real equipment.

 Figure 10 (1 and 2) shows two waveforms of optical pulsed signals recorded respectively at the output of the laser radiation source (pos. 1 of Fig. 10) and at the output of ACF 16 in one of the partial reception angles at the corresponding output of one of the photosensitive photodetector elements MFP 22 (item 2 of figure 10). In this case, the optical signal at the input of ACF 16 was significantly attenuated and amounted to no more than a few photons in level (2 quanta in the diffraction angle of reception). The time coordinate is plotted along the abscissa, and the normalized signal amplitude is plotted along the ordinate. The second oscillogram shows random spikes in the amplitude of the optical signal at the output of the ACF 16 due to spontaneous emission from the ACF. In this case, the amplitude spike in the second oscillogram of Fig. 10 pos. 2, corresponding in time to the received optical pulse from the laser generator in the first waveform, can be detected with a high probability of correct detection when measuring a statistical parameter, for example, the total duration of all emissions over a fixed level within a given period of time corresponding, for example, to an interval of one cell in figure 10, position 2. The probability of detecting the indicated surge (impulse) in the second waveform of figure 10 (position 2) is close to 100% when using the a married method based on the analysis of statistical parameters (emissions) of random signals at the output of the ACF. At the same time, the detection of an optical signal based on a given outlier by the signal amplitude analysis method is characterized by a lower detection probability, since this outlier (impulse) in FIG. 10 pos. 2 at the output of the MFP 22 is characterized by a small signal to noise ratio (of the order of q = 1.5), at which the detection probability is ~ 70%. Thus, the proposed method has a higher probability of detecting weak optical signals in comparison with methods for receiving signals based on the analysis of the amplitudes of the signals at the output of the photodetectors. According to experimental estimates and based on a comparison with the noise level of the ACF in the registered optical output signal corresponding to the amplitude spike in the second waveform of FIG. 10, pos. 2, no more than two photons (quanta) from the radiation generated by the laser generator were contained at the input of the ACF. The use of laser radiation with a long duration and the simultaneous reception and registration of several pulses-emissions, similar to that shown in figure 10 pos. 2, can further increase the probability of detection and increase the range of the laser location system.

 In FIG. 11 (items 1 and 2) shows the nature of the distribution of signals obtained experimentally at the output of the MFP 22 when receiving and recording weak optical signals from an extended object (model).

 At the same time, at the output of the MFP 22 in the summation block of poses 25, the specified threshold level is simultaneously exceeded at several partial angles of signal reception, and the obtained two-dimensional distribution corresponding to the observed object is displayed on the information processing unit 28. In Fig. 11 (1 and 2) the observed object was, respectively, in the center and on the edge of the field of view of the receiving channel. Thus, in the device that implements the method, a high sensitivity corresponding to the quantum limit is realized when imaging objects in a wide field of view corresponding to the number of elements in the MFP 22 photodetector equal to 128 x 128 elements.

Application of the proposed laser location method and device for its implementation allows to obtain the following results:
- to provide an increase in the sensitivity of reception of weak optical signals with a long pulse duration and bring the sensitivity level of the reception of these signals to the quantum limit, limited by the quantum structure of the electromagnetic field;
- to increase the efficiency and range of the laser ranging system by increasing the duration of the laser pulses to illuminate the object while ensuring high sensitivity of their reception and at the same time providing extremely high realizable power of the laser radiation source;
- increase the probability of correct detection of the object by using the method of measuring the current deviations of the statistical parameters of radiation at the output of the ACF, as well as by using as a reference signal a specially generated signal-analogue of the received radiation, taking into account factors affecting the attenuation and change of laser radiation to illuminate the object when it is distributed along the highway and reflected from the object;
- to realize high noise immunity from external background radiation and interference, and at the same time provide a threshold level of noise immunity with spectral brightness exceeding the brightness of solar radiation at a working wavelength.

Sources of information
1. German patent N 768068, 03/22/1940.

 2. German patent N 892772, 12.19.1950.

 3. England patent N 604429, 07/05/1948.

 4. US patent N 2624876, 6.01.1953.

 5. US patent N 2678997, 05/18/1954.

 6. USSR Auto Certificate N 146803 of July 25, 1956, bull. N 9, 1962.

 7. Siforov V.I., Sudakov S.S. and other radio receivers. Edited by V. Siforov - M .: Owls. radio, 1974, p. 491 - 496.

 8. Malashin M.S. et al. Fundamentals of designing laser location systems. - M.: Higher School, 1983, p. 98 - 100.

 9. RF patent N 2152056, publ. 06/27/2000, bull. N 18 (prototype).

 10. USSR author's certificate N 669976 of 03/21/1977, "Electron-beam light-modulating tube", Mankevich SK, Stavrakov GN and etc.

 11. "Quantum Electronics", 6, N 11, 1979, "The resolving power of the electron beam spatial light modulator based on the DCDR crystal", Malshakov VG, Mankevich SK, Parygin VN and etc.

 12. Tikhonov V.I. Emissions of random processes. - M.: Science, 1970.

Claims (16)

1. The method of laser ranging, which consists in the formation of laser radiation, highlighting the object, receiving radiation reflected from the object, spectral selection and amplifying it at the working wavelength λ _slave using the spectral selector - an active quantum filter (ACF), dividing the radiation flux into partial flows, setting the spatial partial angle of reception of each of the partial radiation fluxes equal to the diffraction angle of receiving signals at the output of the ACF, the direction of each of the partial flows from the passage of the ACF to the corresponding partial photosensitive element of a multi-element photodetector (MFP) and deciding on the presence of an object by comparing the optical signals at the output of the ACF with a threshold level, characterized in that it simultaneously modulates the laser radiation in time and is formed on the basis of a modulated laser radiation optical signal-analogue of the received radiation, determine its duration T _a , convert it into an electrical signal-analogue of the received radiation I memorize this analog signal through a memory unit, measure the statistical parameter of optical radiation at a working wavelength λ _slave in each partial spatial reception angle at the ACF output by analyzing the signals at the MFP output, determine the average value of the statistical parameter of optical radiation over all spatial partial the angles of reception at the output of the ACF, then during the reception of radiation reflected from the object, in each of the partial angles of reception at the output of the ACF determine the deviation of the statistical parameter of optical radiation from the average value of this statistical parameter of optical radiation and form the function of the deviation F (t) in time equal to the difference between the current values of the statistical parameter of optical radiation and the average value of the statistical parameter of optical radiation, the current time summation of the values of the deviation function F (t) in the time interval t _s, equal to the duration t _and analogue optical signal received radiation, carried cf. of this sum Z ₁ in the time interval T _with a first predetermined threshold level P ₁ was simultaneously formed cross-correlation function K (t) between the stored electric received radiation-analog signal, and the generated F (t) the deviation function at the time interval T _s, equal to the duration T _{a of the} optical signal-analogue of the received radiation, compare the cross-correlation function K (t) with the second predetermined threshold level P ₂ , decide on the presence of the object or if the sum Z ₁ exceeds the first a given threshold level P ₁ , or when the cross-correlation function K (t) exceeds the second predetermined threshold level P ₂ , or at the same time that both of these conditions are fulfilled in one or simultaneously in several partial spatial reception angles at the ACF output. 2. The method according to p. 1, characterized in that the time modulation of the generated laser radiation is carried out by changing the absorption time of the optical radiation inside the resonator of the laser radiation source at a working wavelength λ _slave , the law of changing the absorption time being set in accordance with a change in time of the signal of the modulating generator. 3. The method according to p. 1, characterized in that the formation of the optical signal analogue of the received radiation is carried out by branching part of the generated and modulated laser radiation, the branch part of the radiation is subjected to Fourier transform and weaken it by χ times, and the attenuation coefficient χ is chosen in accordance with formula

where L is the estimated range to the object;
Q is the divergence of the laser radiation generated by the laser source to illuminate the object;

the area of the entrance pupil (aperture) of the receiving telescope, D _T is the diameter of the receiving telescope;
S _about - the estimated effective area of the reflecting surface of the object;
ε _about - the estimated coefficient of reflection of radiation by the surface of the object;
ε ₂ - transmittance of radiation in the atmosphere at the working wavelength λ _slave , equal to
ε ₂ = exp [-α _p • L _a ],
where α _p is the spectral absorption coefficient of radiation by the atmosphere for the working wavelength λ _slave , L _a is the length of the estimated path of radiation in the atmosphere to the object and in the opposite direction from the object;
ε ₃ - transmittance of radiation in the atmosphere, due to scattering by inhomogeneities of the atmosphere at the working wavelength λ _slave , equal to ε ₃ = exp [-α _p.m. • L _a ], where α _p.m. - coefficient of molecular dispersion of radiation in the atmosphere at a working wavelength λ _slave .
4. The method according to p. 1, characterized in that as the statistical parameter of optical radiation using the number of random emissions of the amplitude of the optical radiation per unit time over an arbitrarily selected fixed level.  5. The method according to p. 1, characterized in that as the statistical parameter of the optical radiation using the total duration of the random emission of the amplitude of the optical radiation per unit time over an arbitrarily selected fixed level. 6. The method according to p. 1, or 4, or 5, characterized in that as a unit of time when measuring the statistical parameter of optical radiation, a period of time equal to or a multiple of the time constant of the active quantum filter ACF t _p inversely proportional to the value of f _o strip quantum gain ACF: t _p = 1 / f _o
7. The method according to p. 1, characterized in that for the formation of the values of the first and second predetermined threshold levels P ₁ and P ₂ , the generated optical signal analog of the received radiation is directed to the optical input of the ACF, subjected to spectral selection and amplification at the operating wavelength λ _slave ACF, each of the partial space receiving the output angles ACF determine statistical parameter of optical radiation at the operating wavelength λ _slave, determining an average value of optical radiation for all statistical parameter the spatial spatial angles of reception at the output of the ACF, in one of the partial angles of reception corresponding to the angular direction of the optical signal analogous to the received radiation directed to the optical input of the ACF, the current time deviation of the statistical parameter of optical radiation from the average value of this statistical parameter of optical radiation is determined as a function time and form the deviation function F ₂ (t) equal to the difference of the current values S (t) of the statistical parameter of optical radiation I and its average value S _o (F ₂ (t) = S (t) - S _o ), carry out the current time summation of the values of the deviation function F ₂ (t) over a time interval T _s equal to the duration of the generated signal-analogue of the received radiation , the resulting sum Z _{2 is} taken as the value of the first predetermined threshold level P ₁ = Z ₂ , at the same time, a cross-correlation function K ₂ (t) is formed between the stored electrical signal-analogue of the received radiation and the generated deviation function F ₂ (t) in the time interval Δt, _with equal durations T Sig la analog received radiation Δt = T _c, determine the maximum value of the cross correlation function K ₂ (t): M ₂ = max {K ₂ (t)} and the resulting value M ₂ is taken as the second predetermined threshold level P ₂ = M ₂ . 8. A laser location device for implementing the laser location method, comprising a laser source installed on the first optical axis at a working wavelength λ _slave with a pump unit, a swivel mirror with a mirror drive and a mirror drive control unit, a receiving telescope mounted on the second optical axis, an input connected with a rotary mirror, the first reflective mirror with a displacement unit, an active quantum filter (ACF) with a pumping and filling unit with a working substance, a concave mirror, a second reflection dowel mirror, polarization filter, interference filter, multi-element photodetector (MFP) and information processing unit, the outputs of which are connected to the pump unit of the laser radiation source, the pump unit and filling the active substance of the active quantum filter with the working substance, the control unit for the drive of the rotary mirror and the unit for moving the first reflective mirror , characterized in that it includes a block for generating a signal analogous to the received radiation, a block for determining statistical parameters, a correlation block analysis, summing unit, first and second threshold units, first and second threshold level measuring units, duration measuring unit, memory unit, modulating generator, while the optical input of the received signal analog signal generating unit is optically coupled to the optical output of the laser radiation source by of the first translucent mirror, the optical output of the received signal analog signal generating unit is connected to the optical input of the active quantum filter by the first negative pressure mirror, and the electrical output of the received signal analogue signal forming unit is connected to the inputs of the memory unit and the duration measurement unit, the outputs of which are respectively connected to the inputs of the correlation analysis unit and the information processing unit, the control input of the received signal analogue signal forming unit is connected to the output of the unit information processing, the outputs of the multi-element photodetector are connected to the inputs of the unit for determining statistical parameters, the control input of which is is output from the information processing unit, and the outputs to the summing unit and the correlation analysis unit, the control input of the summing unit is connected to the output of the information processing unit, and the output is connected to the first threshold unit and the first threshold level measurement unit, the output of which is connected to the first threshold unit and the control input is connected to the output of the information processing unit, the control input of the correlation analysis unit is connected to the output of the information processing unit, and the output is connected to the second threshold block and the second threshold level measurement unit, the output of which is connected to the second threshold unit, and the control input is connected to the output of the information processing unit, the outputs of the first and second threshold blocks are connected to the inputs of the information processing unit, the output of the modulating generator is connected to the laser radiation source.  9. The laser location device according to claim 8, characterized in that the laser radiation source comprises optically coupled a first mirror of a laser source resonator located in series on an optical axis, an active laser element with a pump unit, a first polarizer, a laser modulation unit, and a second a polarizer and a second resonator mirror of the laser source, while the laser modulation unit is connected to the output of the modulating generator.  10. The laser location device according to claim 8, characterized in that therein the third reflection mirror, the Fourier transforming lens, the diaphragm, the radiation attenuation unit, which are sequentially mounted on the optical axis from the optical input to the optical output of the block receive the signal analogue of the received radiation , the first forming lens, the second translucent mirror recording the photodetector, the fourth reflective mirror, the second forming lens and the fifth reflective mirror, and the control input of the donkey unit radiation Blenheim connected to the information processing unit, and the output of the photodetector is connected to a recording unit and a memory unit duration measurement.  11. The laser location device according to claim 8, characterized in that the statistical parameter determination unit therein comprises emission parameter determination cells by the number of partial elements in the multi-element photodetector, subtraction cells by the number of emission parameter determination cells, a first clock generator, a first switch, an adder and division cell, while the inputs of the cells for determining the emission parameters are connected to the corresponding outputs of the partial photosensitive elements of the multi-element photodetector, and the outputs are connected to the inputs of the subtraction cells and the inputs of the first switch, the second inputs of the subtraction cells are connected to the output of the division cell, the output of the first switch through the adder is connected to the input of the division cell, the cells for determining the emission parameters are connected to the output of the first clock generator, the first clock generator and the cells for determining the parameters of emissions are connected to information processing unit, the control input of the first switch is connected to the information processing unit, the outputs of the subtraction cells correspond to the outputs of the determination unit statistical parameters, as well as to the corresponding outputs of the subtraction cells, the inputs of the correlators are connected, which contains the correlation analysis block.  12. The laser location device according to claim 11, characterized in that in it, in the unit for determining statistical parameters, the cell for determining the emission parameters contains a series-connected amplitude selector, a shaper, first and second counters connected to a switch, a gating cascade and a counter of pulse counters, the inputs of the gating stage are connected to the outputs of the counter pulse generator and the driver, and the output is connected to the second counter, the control inputs of the amplitude selector and the first and second a counter connected to the output of the first clock, a switch control input connected to the output of the information processing unit.  13. The laser location device according to paragraph 8, characterized in that the summing unit contains summing cells - according to the number of partial photosensitive elements in the multi-element photodetector, a second switch and a second clock generator, while the inputs of the summing cells are connected to the corresponding outputs of the subtraction cells of the statistical determination unit parameters, and the outputs are connected to the inputs of the second switch, the output of the second clock is connected to the control inputs of the summing cells, the output of the second commut the torus is connected to the first threshold block and the first block for measuring the threshold level, the control input of the second clock is connected to the output of the information processing unit, the control inputs of the second switch and summing cells are connected to the output of the information processing unit.  14. The laser location device according to claim 13, characterized in that in it, in the summing unit, the summing cell contains a ring switch, memory registers, an output switch, an output adder and a control circuit, while the outputs of the ring switch through the memory registers are connected to the inputs of the output switch the output of which is connected to the output adder, the control input of the ring switch through the control circuit is connected to the output of the information processing unit, and the control input of the output switch is connected to ode second clock.  15. The laser location device according to claim 8, characterized in that the correlation analysis unit contains correlators for the number of partial photosensitive elements in the multi-element photodetector and a third switch, the output of which is connected to the second threshold unit and the second threshold level measurement unit, while the inputs correlators are connected to the corresponding outputs of the subtraction cells of the unit for determining statistical parameters, the second inputs of the correlators are connected to the output of the memory block, the outputs of the correlators are connected s to the inputs of the third switch, the control input of which is connected to the output of the information processing unit.  16. The laser location device according to claim 15, characterized in that in it in the correlation analysis unit the correlator comprises optically coupled light source, a beam expander, an acousto-optic modulator, a first lens, a first spatial filter, a second electronically modulating lens on the optical axis a beam tube (SELT), a third lens, a second spatial filter, a photodetector, the output of which is connected to an intermediate memory unit, as well as a ring switch, memory registers, a switch, a control circuit, an intermediate frequency generator, and an amplifier, while the outputs of the ring switch are connected through the memory registers to the inputs of the output switch, the output of which through the intermediate frequency generator is connected to the control electrode of the acousto-optic modulator, and the control input to the information processing unit, control input ring switch through a control circuit connected to the output of the information processing unit, the SELT control electrode through an amplifier connected to the output unit and the memory, the input of the ring switch is connected to the output of the corresponding subtraction cell of the unit for determining statistical parameters, and the output of the intermediate memory unit is connected to the corresponding input of the third switch.  17. The laser location device according to claim 15, characterized in that in it, in the correlation analysis unit, the correlator comprises a ring switch, memory registers, an output switch, a control circuit, first, second and third fast Fourier transform (FFT) processors, a multiplier and a register memory of the standard, while the outputs of the ring switch through the memory registers are connected to the inputs of the output switch, the output of which is connected to the input of the first FFT processor, and the control input is connected to the output of the information processing unit, the course of the first FFT processor is connected to the first input of the multiplier, the output of the second FFT processor through the reference memory register is connected to the second input of the multiplier, the output of which is connected to the input of the third FFT processor, the output of which is connected to the corresponding input of the third switch, the input of the second FFT processor is connected to the output of the unit memory, the control input of the ring switch through the control circuit is connected to the output of the information processing unit, and the input is connected to the corresponding subtraction cell of the definition unit ELENITE statistical parameters.  18. The laser location device according to claim 8, characterized in that the duration measuring unit therein comprises an amplitude selector first and second shapers, first and second gate stages, first and second counters, a counting pulse generator, an inverter and an adder, the amplitude selector and the first shaper is formed by rectangular pulses corresponding to elementary pulses in the optical signal-analogue of the received radiation, which is formed at the output of the block for the formation of the signal-analogue of the received radiation I, while the output of the amplitude selector is connected to the input of the first shaper, the output of which is connected to the inverter and the first gate stage, the output of which through the first counter is connected to the first input of the adder, from the output of which a signal corresponding to the total duration of the analog signal of the received radiation is supplied to the unit information processing, the inverter output through the second driver is connected to the input of the second gate stage, the output of which through the second counter is connected to the second input of the adder, count pulse generator is connected to the second inputs of the first and second gating stages.

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