RU2610832C1 - Method and station of resonance radio detection and location - Google Patents

Abstract

FIELD: radar ranging.

SUBSTANCE: invention relates to resonant radio location and detection based on the known phenomenon of abrupt increase in the amplitude of the probing radio signal reflected from an aircraft at the wave length that is equal to the double the value of the size of the aircraft’s airframe and/or resonating elements, for example wings and suspended structures, and can be used in an air traffic control system. Said result is achieved due to the following:preliminary selection of the frequency band, covering the resonance range of both aerodynamic and ballistic aircrafts; periodic frequency scanning of air to receive, select and rank the allowable probe frequences in the selected band that are free of radio noise; ranking of the allowable probe frequencies, which are free of radio noise, in the order of their proximity to the center of the frequency band of the resonating of the aircraft; successive radiation in each probing cycle at long range and short radio pulses at different frequencies within the currently permitted range for detecting the aircraft in the far zone and resolution of marks from the aircraft in the near zone of detection respectively; reduced divergence of radio beam in the elevation plane in the moments of radiating long radio pulses to increase energy density in the radio beam and further increase in the aircraft detection range; automatic switch to spare frequencies in the order of their ranking in case of active noise at the frequency of probing; parallel processing of resonance signals throughout the dedicated zone of air space.

EFFECT: technical result is increased efficiency of resonant radar maintenance of aircraft movement and bigger number of serviced types of aircrafts.

16 cl, 5 dwg

Description

Technical field

The invention relates to the field of resonant radar and can be used in an air traffic control (ATC) system for early detection and recognition of aircraft.

State of the art

Known methods and means of resonant radar [1-3], based on the use of electromagnetic waves (EMW) with a wavelength

where L is the geometric size of the aircraft and / or its structural resonating elements (wings, fuselage, suspension structures).

The positive quality of resonant radar is the increased (≥10) magnitude of the reflected radio signal compared to the value of the effective scattering surface (EPR) for diffuse reflection of the radio signal from the aircraft. The consequence of this according to the theory of radar [4] is the increased detection range of the aircraft.

Another positive quality of resonant radar is the automatic protection against STELS anti-radar technology in the resonant wavelength range (1) for large (L≥0.5 m) aircraft. This is due to the fact that in order to create radio invisibility of an aircraft, the thickness of the radar absorbing coatings must be a multiple of λ / 4. Under conditions of (1) resonance, the weight of the radar absorbing coatings may exceed the weight of the aircraft itself. Such an aircraft becomes unbearable and incapable of movement in the air.

Despite significant advantages, resonant radar has not yet been widely used.

This is due to the fact that in the indicated (1) resonance range of typical aerodynamic and ballistic aircraft, there are many industrial sources of radio emissions and communication equipment that impede the resonant detection of aircraft.

In addition, to obtain radar data (RLD) about the air situation, comparable in accuracy of measuring angular coordinates with a radar station (radar) of the centimeter range of EMW, the meter (1) range of EMW used in resonant radar is associated with increased dimensions of antenna systems and requires solving problems reduction of windage of the latter, resistance to wind loads and seasonal movement of soils.

It is advisable to use the positive qualities of resonant radar, namely the increased detection range of aircraft and protection against anti-radar technology in the interest of increasing the performance of air traffic services.

Prototype of the invention

The closest in purpose and technical essence to the claimed invention relates to a method and means of resonant radar [3].

According to [3], the known method of resonant radar includes sensing the airspace of the probable location of aircraft (LA) by pulsed electromagnetic radiation in the frequency range of resonant reflections from the aircraft, receiving the reflected resonant echo signals, converting them into digital form, primary and secondary processing of digitized echo signals.

Moreover, due to the increased interference situation in the long-wavelength EMF range, the frequency range (1) of the working resonant frequencies [2] is limited to the detection of only small-sized unmanned aerial vehicles (UAVs). In the process of sensing and receiving radio signals, sequential scanning of a given sector of the airspace with a narrow transceiver radio beam antenna with an electromechanical drive and / or electronic scanning is used. In each angular direction of sounding, a continuous frequency scan is performed to transmit and receive sounding signals (ZS) in the entire range of UAV resonance reflections from minimum to maximum values. In the process of receiving reflected signals at the current frequency and correlation signal processing, the amplitude of the received signals is compared with the amplitude of the signals of the previous frequency sounding. The decision to detect the aircraft is made according to the maximum value of the amplitude of the received signal. For the detected aircraft, the numerical value of the resonant wavelength (λ _res ) is recorded and the dimensions “L _res ” of the aircraft are determined from condition (1) at λ = λ _res . The found value of L _{res is} then compared with the sizes of typical aircraft and decisions are made on the type of detected aircraft according to the coincidence of the numerical value of L _res with the specific reference value “L _et ” of the aircraft. At the same time, the distance to the aircraft is measured by the time delay of the arrival of the maximum signal from the aircraft relative to the moment of emission of the probe signal and the angular position (azimuth and elevation angle) of the aircraft is measured by the angular position of the probe beam at the time of its resonance reflection from the aircraft.

The disadvantages of the prototype

A disadvantage of the known method of resonant radar is the reduced performance of the airspace survey due to sequential viewing by a narrow beam and sequential scanning of the carrier frequency in each scan cycle in range and in each direction of sounding.

Another disadvantage of this method is the difficulty of the resonant detection of aircraft in radio interference due to the algorithm used in [3] for continuous frequency scanning with a carrier sounding frequency and continuous viewing of the entire range of UAV resonant frequencies.

Another disadvantage of the known method of resonant radar is the reduced detection range of large aerodynamic aircraft (airplanes, helicopters), associated with the use in [3] of only the short-wavelength range of resonant reflections (1) characteristic of UAVs.

The reduced detection range of large-sized aircraft in this case is determined by the reduced EPR due to diffuse rather than resonant reflection of electromagnetic waves from such aircraft.

Reducing the detection range of large aircraft in turn makes it difficult to detect all types of aircraft in a timely manner, limits the time for trajectory processing of their motion parameters, reduces the reliability of radar data, and makes it difficult to maintain and control the air traffic of the aircraft.

In general, these technical drawbacks of the known [3] resonant radar method reduce the performance of aircraft air traffic maintenance.

The objective of the invention is to increase the performance of resonant radar for servicing aircraft air traffic.

The technical result that provides the solution to this problem is to expand the capabilities of the resonant airspace survey in terms of the speed of the survey and the number of aircraft types served. SUMMARY OF THE INVENTION

The solution of this problem and the achievement of the claimed technical result is ensured by the fact that the resonant radar method includes sensing the airspace of the probable location of aircraft (LA) by pulsed electromagnetic radiation in the frequency range of resonant reflections from the aircraft, receiving the reflected resonant echo signals, converting them into digital form, primary and secondary processing of digitized echoes.

и

зондирования, достаточные для одновременного обнаружения аэродинамических и баллистических ЛА одновременно по всему сектору обзора воздушного пространства, на одной из выбранных частот формируют длинный зондирующий сигнал (ЗС1) с уменьшенной расходимостью в горизонтальной плоскости для обнаружения ЛА в дальней зоне сектора обзора, на другой частоте - короткий зондирующий сигнал (ЗС2) увеличенной расходимости для обнаружения и разрешения ответных сигналов от ЛА по дальности в ближней зоне сектора обзора, сформированные зондирующие сигналы модулируют по частоте по линейному закону и последовательно излучают их с периодом Т повторения одновременно по всему полю обзора воздушного пространства в виде множества лопатообразных линейно-частотно-модулированных (ЛЧМ) радиолучей, в каждом периоде Т зондирования излучают вначале длинный (τ1) ЛЧМ сигнал ЗС1 и затем с задержкой τ_зад - короткий (τ2) ЛЧМ сигнал ЗС2, после излучения ЛЧМ сигналов в течение времени радиомолчания передатчиков ЗС на каждом периоде Т производят прием резонансных ЛЧМ эхосигналов (ЭС), отраженных от ЛА, одновременно по всему полю обзора воздушного пространства азимутальным и угломестным приемными каналами, в процессе приема отраженных резонансных эхосигналов принятые сигналы в каждом приемном канале разделяют по частоте

и

для параллельной обработки коротких и длинных ЛЧМ ЭС, усиливают их, переносят на промежуточную частоту и преобразуют в цифровую форму, в процессе преобразования сигналов в цифровую форму оцифрованные потоки ЛЧМ ЭС преобразуют в формат представления с плавающей точкой, в процессе первичной обработки оцифрованные ЛЧМ ЭС подвергают квадратурной обработке для уменьшения поляризационных потерь энергии принятых сигналов, сжимают их внутриимпульсной ЛЧМ-обработкой для повышения разрешения отметок от ЛА по дальности, измеряют дальность D до ЛА путем пошагового сдвига по дальности и взаимной корреляционной обработки зондирующего и принятого сигналов и путем регистрации дальности до ЛА по моменту максимума корреляционной функции, одновременно измеряют угловые координаты ЛА по азимуту β и углу места ε путем пошагового сдвига фазы и корреляционной обработки амплитудно-фазового распределения сигналов в азимутальном и угломестном каналах приема и путем регистрации углового направления на ЛА по максимуму взаимной корреляционной функции в соответствующих угловых направлениях, параллельно проводят межпериодное когерентное накопление обработанных сигналов, режекцию пассивных помех и пороговую обработку сигналов для выделения сигналов от ЛА на фоне помех, сигналы от ЛА, прошедшие пороговую обработку, фильтруют по доплеровской частоте и определяют радиальную (Vr) скорость ЛА по частоте Доплера, соответствующей максимальному значению амплитуды сигнала, найденные значения Vr, D, β, ε для каждого ЛА в виде многоразрядных последовательностей цифровых сигналов передают на вторичную обработку, а в процессе вторичной обработки оцифрованных эхосигналов проводят их идентификацию, привязку к сигналам ЛА в соответствующих разрядах их цифровых последовательностей идентификационных адресов и сигналов единого времени, рассчитывают траекторию и курсовую скорость V_к движения каждого ЛА, сравнивают найденные параметры движения ЛА с банком данных параметров типовых ЛА и по результатам их совпадения принимают решение о распознавании конкретного типа ЛА и параметров их движения, результаты траекторной обработки отображают на мониторе и в масштабе единого времени передают внешнему пользователю радиолокационной информации в виде цифрового потока радиолокационных данных (РЛД).According to the invention, before the start of sounding, the optimum range Δf _{opt of the} resonant sounding frequencies is selected, in which they search for frequencies that are free from active interference, rank them in order of priority according to the proximity of the frequencies to the center frequency of the optimal range of resonant frequencies, and form a ranked set Δf of _RZS frequencies for for detecting aerodynamic and ballistic aircraft, in the ranked frequency band, two working hours spaced apart in frequency are selected in priority order then you

and

soundings sufficient for simultaneous detection of aerodynamic and ballistic aircraft simultaneously over the entire sector of the airspace survey, at one of the selected frequencies a long sounding signal (ZS1) is formed with a reduced divergence in the horizontal plane for detecting aircraft in the far zone of the field of view, at a different frequency - short probing signal (ЗС2) of increased divergence for detecting and resolving response signals from aircraft in range in the near zone of the field of view, formed probing signals the channels modulate in frequency according to a linear law and sequentially emit them with a repetition period T simultaneously across the entire field of view of the airspace in the form of a plurality of spade-shaped linear-frequency-modulated (LFM) radio beams, in each sounding period T initially emit a long (τ1) LFM signal ЗС1 and then with a delay of τ _ass - short (τ2) LFM signal ZS2, after radiation chirp signals during a time radiosilence AP transmitters in each period T reception produce resonant chirped echo (ES) reflected from LA odnov TERM around the field of view of the airspace receiving azimuth and elevation channels, in the process of receiving the reflected echo signals received resonance signals into each receiving channel are separated in frequency

and

for parallel processing of short and long LFM ES, they are amplified, transferred to an intermediate frequency and digitized, during the conversion of signals into digital form, the digitized streams of the LFM ES are converted into a floating point representation format, during the initial processing, the digitized LFM ES are subjected to quadrature processing to reduce the polarization energy loss of the received signals, compress them by intrapulse LFM processing to increase the resolution of the marks from the aircraft in range, measure the range D to LA by means of a stepwise shift in range and mutual correlation processing of the probing and received signals and by recording the range to LA by the moment of the maximum of the correlation function, simultaneously measure the angular coordinates of the aircraft in azimuth β and elevation angle ε by stepwise phase shift and correlation processing of the amplitude-phase distribution of signals in the azimuthal and elevation reception channels and by recording the angular direction on the aircraft to the maximum of the mutual correlation function in the corresponding angular directions x, in parallel, they carry out inter-period coherent accumulation of the processed signals, rejection of passive interference and threshold processing of signals to isolate signals from the aircraft against the background of interference, signals from the aircraft that have passed threshold processing are filtered by the Doppler frequency and the radial (Vr) speed of the aircraft is determined by the Doppler frequency, corresponding to the maximum value of the signal amplitude, the found values of Vr, D, β, ε for each aircraft in the form of multi-digit sequences of digital signals are transmitted for secondary processing, and in the secondary the processing of the digitized echo signals carries out their identification, reference to the aircraft signals in the corresponding bits of their digital sequences of identification addresses and signals of uniform time, the trajectory and the heading speed V _{to the} movement of each aircraft are calculated, the found motion parameters of the aircraft are compared with the data bank of parameters of typical aircraft and according to their results coincidences decide on the recognition of a specific type of aircraft and the parameters of their movement, the results of the trajectory processing are displayed on the monitor and on a single the belts transmit to the external user the radar information in the form of a digital radar data stream (RLD).

The choice of the optimal range Δf _{opt of the} resonance sensing frequencies eliminates the need to view the resonance frequency range for each dimension of the serviced aircraft separately and limit themselves to the frequency intersection of these ranges, in which the resonant EPR for all serviced aircraft is not lower than the specified value for detection in the far detection zone. The consequence of this is a reduction in the time for a frequency review of the served corner sector of the airspace.

Preliminary (before the start of sounding) search in the selected optimal range Δf _{opt of} carrier frequencies free from active interference, ranking them in order of priority by the proximity of frequencies to the center frequency of the optimal range of resonant frequencies and the formation of a ranked range Δf of the _SPS frequencies for the resonance detection of aerodynamic and ballistic aircraft additionally, it is possible to eliminate the time loss for tuning the carrier frequencies from interference in the process of receiving signals and to provide a quick transition to a free carrier sounding frequency, rational from the point of view of sufficiency of EPR for aircraft maintenance, in the event of barrage or industrial active interference at the sounding frequency.

и

зондирования, достаточных для одновременного обнаружения аэродинамических (авиационных) и баллистических ЛА одновременно по всему сектору обзора воздушного пространства, позволяет, с одной стороны, исключить необходимость частотного сканирования несущей частотой зондирования и, с другой, - обеспечить параллельный прием и первичную обработку сигналов от двух видов ЛА, резко отличающихся по своим скоростным параметрам и траектории полета.The choice in the ranked range Δf of the _RZS frequencies in the order of priority according to the EPR of two operating frequencies spaced apart from each other in frequency

and

soundings sufficient for simultaneous detection of aerodynamic (aviation) and ballistic aircraft simultaneously over the entire airspace survey sector, allows, on the one hand, to eliminate the need for frequency scanning by the carrier frequency of sounding and, on the other hand, to provide parallel reception and primary processing of signals from two types LA, sharply differing in their speed parameters and flight paths.

In general, the indicated technical advantages, as well as the parallel reception, digitization, and processing of resonant echo signals simultaneously over the entire field of sounding of airspace, make it possible, in comparison with the prototype, to expand the capabilities of the resonant view of airspace in terms of the speed of view and the number of aircraft types served.

The consequence of this is a sharp reduction in the time spent on the resonant detection and processing of aircraft echo signals and an increase in the performance of resonant radar for servicing aircraft air traffic.

The invention is illustrated by the drawings presented in FIG. 1 - FIG. 6.

In FIG. 1 shows the dependence of the amplitude U of the reflected sounding signal (ZS) on the geometric dimensions L of the aircraft and the resonance condition at a fixed frequency of the ZS, in FIG. 2 - dependence of the numerical value of σ of the resonant EPR on the frequency of the ES for aerodynamic (aviation) and ballistic aircraft, in FIG. 3 - the well-known [2] dependence of the numerical value of σ of a small-sized (L = several tens of cm) unmanned aircraft from the AP frequency, in FIG. 4 - an example of a functional diagram of a station that implements the proposed method of resonant radar, in FIG. 5 is a diagram of a reception and an algorithm for primary processing of resonant echo signals.

In FIG. 1-6 are indicated:

1 - antenna system;

1.1 - transmitting antenna-feeder device (AFU);

1.2 - elevated receiving AFU;

1.3 - azimuthal receiving AFU;

2 - multi-channel amplifier of sounding signals (ZS);

3 - multi-channel receiver (PFP) of the response resonant echo signals;

4 - two-frequency generator of long and short linear-frequency-modulated (LFM) ES with the possibility of tuning their carrier frequencies;

5 - device analog-to-digital conversion and quadrature demodulation ES;

5.1 - analog-to-digital converter (ADC);

5.2 - quadrature demodulator (CD);

5.3 - block transmission of digitized ES;

6 - device for primary processing of ES;

6.1 - block receiving digitalized ES;

6.2 - block intrapulse processing (VIO) and compression LFM - ES;

6.3 - block of digital azimuth chart formation (TsFDNA);

6.4 - a block of digital chart formation by elevation (TsFDNU);

6.5 - block coherent accumulation (KN);

6.6 - detector (D);

6.7 - threshold processing unit (POR);

6.8 - block for the formation of signal marks (CO);

6.9 - block suppression of the side lobes in range and azimuth β;

6.10 - digital filter (DF);

6.11 - adder;

6.12 - block forming the coordinate points (CT) of the aircraft;

6.13 - block rejection of passive interference in azimuth (width of the notch zone-SZR) and the range of the notch zone (DZR);

7 - device for secondary processing of ES;

8 - automated workstation (AWP) of the radar operator;

9 - equipment for receiving / transmitting data (ADF) and resonant radar control commands;

10 - bidirectional active interface bus (AL).

The proposed method and the resonant radar station are based on the known [4] resonance phenomenon presented in FIG. 1. According to [4], with the dimensions “L” of the aircraft close to the half-wave vibrator (L = λ / 2), the numerical resonance amplitude U _{cut of the} reflected ES (echo signal - ES) increases sharply (Fig. 1). In this case, the numerical value of the EPR (σ = σ (Ures)) under resonance conditions (1) is more than 10 times higher than the EPR for diffuse reflection of the CS. An experimental estimate of the numerical value σ = σ (Ures) depending on the carrier frequency “f” of the LC with linear frequency modulation (LFM) for the three main types of large-sized aerodynamic (aviation) and ballistic aircraft with sizes L1, L2 and L3, respectively, is presented in FIG. . 2.

From FIG. 2 it can be seen that, in contrast to the known [3] resonance radar method for detecting aircraft with σ≥3 m ^2, there is no need to change the carrier frequency of the GL in the entire spectrum (Fig. 3) of the resonance reflections of each aircraft individually. To do this, it is enough to limit ourselves to one carrier frequency f1 lying in the frequency band Δf _opt (Fig. 2), common to aerodynamic (aviation) and ballistic aircraft.

At the same time, in order to increase the performance in the proposed method of resonant radar, a parallel location was used simultaneously at two carrier frequencies f1 and f2 with the possibility of their tuning in the range Δf _opt . The need for such tuning is associated with the work in the specified range of many radio stations and radio communications with frequency tuning. Therefore, to ensure the operability of resonant radar in the conditions of interference in the proposed method, before scanning and periodically in the process of processing response resonant echo signals in the Δf _opt range, a frequency scan (at reception) of the selected airspace sector is performed to identify sources of interference, selection and ranking of AP frequencies, free of interference in real time.

In view of the above, the optimal value of the frequency range Δf _{opt of the} resonant radar is selected from the condition of minimum intersection of the resonance reflection regions at the EPR level of at least a given value, for example 3 m ² :

где:

Where:

- пересечение частотных областей

всех I-х типов ЛА;

- intersection of frequency domains

all I types of aircraft;

- резонансная полоса частот i-го типа ЛА;

- resonant frequency band of the i-th type of aircraft;

- σi is the minimum allowable resonance value of the EPR for the detection of the i-th type of aircraft;

- i, I - the current and maximum value of the types of serviced aircraft, respectively.

An embodiment of a station implementing the proposed resonant radar method is shown in FIG. four.

According to FIG. 4, the resonant radar station contains at least one transmitting and at least two receiving azimuth and elevation antenna-feeder devices (AFUs) mounted on antenna supports [5-7] for multipath sounding of airspace at the resonance frequencies of aircraft (LA) and reception on these frequencies of reflected resonant echo signals and radio interference signals. The input of the transmitting AFU 1.1 through a multi-channel power amplifier 2 is connected to the output of a two-frequency generator 4 of linearly frequency-modulated (LFM) probing signals (LF) of increased and short duration with the possibility of tuning the carrier frequency in the frequency range (2) of the resonance of aerodynamic and ballistic aircraft. The signal outputs of the receiving AFUs 1.2 and 1.3 are connected to the inputs of the receiving superheterodyne devices of the corresponding multi-channel receivers (PFP) 3. The reference inputs of the PFP 3 are connected to the output of the dual-frequency generator 4 ZS, and the signal outputs of the PFP 3 are connected through the device 5 for analog-to-digital conversion and quadrature ES demodulation and through devices of primary 6 and secondary 7 ES processing - with an automated workstation (AWS) 8 of the station operator. The signal and control outputs of AWP 8 through a bi-directional active interface bus 10 are connected to the control inputs of the generator 4 ZS, devices of the primary 6 and secondary 7 processing of resonant ES and through equipment 9 receiving / transmitting data (ADF) - with external consumers of radar information. 12. The device for analog-to-digital conversion and quadrature demodulation of an ES contains a series-connected analog-to-digital converter (ADC) 5.1, a quadrature demodulator (CD) 5.2 and a block 5.3 for transmitting digitized ES. The primary processing unit of the echo signals is capable of parallel processing of the digitized ES from the azimuthal and elevation AFUs and contains the azimuthal 11 and elevation 12 primary processing channels connected via the elevation angle digital block 6.4 and the coordinate unit formation unit 6.12 with the output of the ES primary processing unit 6 . In this case, the azimuthal channel 11 of the primary processing of the ES contains a block 6.1 connected to the reception of the digitized ES, block 6.2 of the in-pulse processing and compression of the LFM ES, block 6.3 of the digital azimuth charting (DPSA), block 6.5 of coherent accumulation, block 6.13 of the passive interference rejection by azimuth and range , detector 6.6, threshold processing unit 6.7, signal marking unit 6.8 and side lobe suppression unit 6.9 in range and azimuth. Primary processing channel 12 contains a series-connected unit 6.1 for receiving digitalized ES with orthogonal polarization from the AFU 1.2, a circuit for recovering the amplitude and polarization of the ES, including two digital filters 6.10 and an adder 6.11, an in-pulse processing and compression module for the LFM ES and block 6.5 for coherent accumulation. Block 6 of the primary processing of echo signals is made of a modular design on programmable logic integrated circuits (FPGA) with a reprogrammable memory and additionally contains a central control and data transmission processor, a master and slave digital processing unit for long and short ES, a synchronizer and an input-output device (not shown in the figures). Block 8 of the secondary processing of echo signals is made according to the standard scheme of an industrial electronic computer on two non-shell computers of the Core i7 series and two expanders - mezzanines of the 4 × 1 Gbit Ethernet and 4 × RS422 series with a block of reprogrammable Gard and Flesh memory. fifteen.

Antenna supports [5-6] AFU 1.1-1.3 are made quickly erected [7-8] and are resistant to wind loads and seasonal movement of soils. They contain at least one supporting mast 1.4 mounted on metal beams - a linear grillage that combines the upper ends of metal screw piles (not shown in the figures). Each screw pile [5-6] is made in the form of a pipe with an insulating non-freezing coating on the basis of a polymer and a screw working element mounted on its lower end for rigidly fastening the lower end of the pile in solid soil below the level of seasonal thawing.

частотой, подаваемые на опорные входы супергетеродинных приемников ПРМ 3, позволяют принять с азимутальной 1.3 и угломестной 1.2 АФУ текущие значения частот f_n, занятых активными помехами, определить угловые направления постановщиков помех и сформировать ранжированный набор (диапазон) Δf_рзс частот, свободных от помех, для резонансного зондирования аэродинамических и баллистических ЛА.In accordance with the proposed method, before the start of sounding in the calculated (2) optimal frequency range Δf _{opt of the} resonant radar, a search for frequencies free of active interference is performed by changing the frequency overview of the airspace of one of the carrier (reference) frequencies of the generator 4 using the program specified in AWP 8 In this case, high-frequency signals with a variable current

frequency supplied to the reference inputs of the PFM 3 superheterodyne receivers, allow taking the current values of the frequencies f _n occupied by active interference with azimuthal 1.3 and angular 1.2 AFUs, determining the angular directions of the jammers and forming a ranked set (range) Δf of the _excitation frequency of the interference-free frequencies, for resonant sounding of aerodynamic and ballistic aircraft.

The formation on the set (2) of a ranked set of Δf _RZS frequencies, free from interference, for resonant sounding of aerodynamic and ballistic aircraft is carried out from the conditions:

Where:

Δf _n is the current value of the range of resonant frequencies occupied by active interference;

fj ^res - the j-th frequency of the probing signals, free from interference at the current time;

f _n - n-th interference frequency in the optimal band of resonant frequencies Δf _opt ;

j, J is the current number of the frequency rank, characterizing the degree of its proximity to the center Δf _opt , and the total number of ranks, respectively;

n, N is the current interference frequency number and the total number of interference frequencies in the resonant frequency band Δf _opt .

After the formation of a ranked set of Δf _RZS probing frequencies in the optimal frequency band Δf _opt frequencies, the found value Δf _RZS in graphical and tabular form is displayed on the workstation 8 monitor of the radar operator.

и

зондирования, достаточные для одновременного обнаружения аэродинамических и баллистических ЛА одновременно по всему сектору обзора воздушного пространства. Переход на другие рабочие частоты f1 и f2 зондирования в диапазоне Δf_рзс производится автоматически по мере появления на рабочих частотах постановщиков помех.The operator AWP 8 in order of priority selects two operating frequencies spaced apart in frequency

and

soundings sufficient for simultaneous detection of aerodynamic and ballistic aircraft simultaneously across the entire airspace survey sector. The transition to other sounding operating frequencies f1 and f2 in the range Δf _{RZS is} performed automatically as _interference producers appear at the operating frequencies.

Then, at the current frequency f1 in generator 4, a long probing signal (ЗС1) is formed with a reduced divergence in the vertical plane for detecting aircraft in the far zone of the viewing sector, at another frequency f2, a short probing signal (ЗС2) is increased divergence for detecting and resolving response signals from Aircraft in range in the near field of view.

The generated probing signals 3C1 and 3C2 modulate in frequency according to a linear law, branch into many amplifier channels of the power amplifier 2. In amplifier 2, the probing signals 3C1 and 3C2 are amplified in power. In the process of amplification of ZS1, a phase shift of 180 ° is introduced into the separate amplifier channels of amplifier 2 to reduce the divergence of the radio beam of the transmitting AFU 1.1 in the vertical plane.

The amplified ZS1 and ZS2 are emitted by AFU 1.1 log-periodic antennas (HLA) with a period of одновременно repeating simultaneously over the entire field of view of the airspace in the form of a plurality of spatula-shaped linear-frequency-modulated (LFM) radio beams. In each period Τ of the sensing of the LPA AFU 1.1 emit initially a long (τ1) LFM signal ЗС1 with a narrow Δε _y ≈45 ° (in the vertical plane relative to the horizon) radiation pattern and then with a delay τ _back - a short (τ2) LFM signal ЗС2 with a wide Δε _w ≥90 ° (in the vertical plane relative to the horizon) by the radiation pattern.

In this case, to reduce polarization, information and energy losses, the planes of the shovel-shaped rays of neighboring LFU AFU 1.1 are deployed relative to each other and to the horizon at an angle of 45 °, and the angular dimensions Δβ of the rays of each LFB in the azimuthal plane when both long and short ES are emitted, are chosen the same and are Δβ = 90-120 °.

The numerical values of the period of Τ following the probing LFM signals, the divergence Δε _y and the duration τ1 of the first probing LFM signal ЗС1 are selected from the condition for detecting the aircraft at the maximum range D _{max with a} long (τ1) probe signal with a narrow Δεy in the elevation plane of its directional pattern:

Where:

c = 3 × 10 ⁸ km / s is the propagation velocity of electromagnetic waves;

Рзс1 - power density of the first (ЗС1) probe LFM pulse of increased duration;

Δεy, Δβ is the total scattering angle of radiation ZS1 in the resonant EMW range in the elevation and azimuthal plane, respectively;

σ = 3 m - the minimum size of the EPR at resonant reflection of ZS1;

Emin = 10 ^-13 J / cm ² - the sensitivity of the receiving devices.

The duration τ2 of the second probing LFM signal ЗС2 and its time delay Δτ relative to ЗС1 are selected from the conditions of the possibility of resolving the echo signals in range and separate Δr _{min of} observing the aircraft in each angular direction:

Where:

t _per - the duration of the transient processes in the transmitting path after the radiation of the first ZS 1.

After the LFM radiation of the signals ЗС1 and ЗС2 during the radio silence time of the power amplifier 2 on each period T, the resonant LFM echo signals ЭС1 and ЭС2 reflected from the aircraft are received at the current carrier frequencies f1 and f2, respectively. Reception of ES1 and ES2 is carried out simultaneously by all receiving elements (cruciform vibrators of Nadenenko) angular AFU 1.2 and azimuthal AFU 1.3 and simultaneously throughout the field of view of airspace. The received amplitude-phase distributions of ES1 and ES2 at the aperture of AFU 1.2 and AFU 1.3 are transmitted to the corresponding multichannel superheterodyne receivers 3. In the process of receiving reflected resonant echo signals, the received signals in each receiving channel are separated by the frequency f1 and f2 for parallel processing of short and long LF EMs. Received ES1 and ES2 in receivers 3 are amplified and transferred to an intermediate frequency. Further, the streams of these signals in the devices 5 azimuthal and elevation receiving channels are digitized, converted into a representation format with a floating point. Further, to reduce the polarization energy loss of the received signals, the digitized LFM ESs are subjected to quadrature processing and transferred to the device 6 for primary ES processing. To increase the degree of resolution of marks from the aircraft in range in blocks 6.2 of the azimuthal and elevation channels for receiving LFM, ESs are compressed by means of their intrapulse processing (VIO). Before compressing the LFM ES in the elevation receiving channel (blocks 6.10 and 6.11), the amplitude and phase of the LFM ES received by the cross-shaped antennas with orthogonal polarization are restored. The measurement of the range "D" to the aircraft in the device 6 is carried out by stepwise shift in range, mutual correlation processing of the probing and received signals and recording the range to the aircraft at the time of the maximum correlation function (not shown in the figures). Further, in blocks 6.3 of the DSCA and 6.4 DSCA devices 6 measure the angular coordinates of the aircraft in azimuth "β" and elevation angle "ε", respectively, by step-by-step phase shift and correlation processing of the amplitude-phase distribution of signals in the azimuthal and elevation reception channels and by recording the angular direction to Aircraft according to the maximum of the mutual correlation function in the corresponding angular directions. In blocks 6.5 of both receiving channels, inter-period coherent accumulation of processed signals is performed. In the azimuthal receiving channel, passive interference is additionally rejected (block 6.13) by limiting the viewing area (narrowing the signal processing volume) by azimuth (SZR) and range (SZR), detection (block 6.6) and threshold processing (block 6.7) to extract signals from LA on the background of interference. The signals from the aircraft that have passed the threshold processing are filtered in block 6.8 by the set of permissible frequencies and the radial (Vr) speed of the aircraft is determined by the Doppler frequency corresponding to the maximum value of the signal amplitude. Then, in block 6.9 of the azimuthal channel for processing digital signals, side lobes and false signals in range and azimuth are suppressed. When measuring the angular ε position of the aircraft in block 6.4 CFDNU additionally use the data of the amplitude-phase distribution in the elevation plane with the azimuth AFU 1.3. Next, in block 6.12, the formation of coordinate points (Vr, D, β, ε) of the aircraft is performed.

In the process of forming coordinate points (Vr, D, β, ε), a topocentric coordinate system is used, in which the center of coordinates is located at point O near the Earth’s surface with geodesic coordinates B - latitude, L - longitude, Η - height, whose x and y axes are located in a plane parallel to the tangent plane to the surface of the Krasovsky ellipsoid passing through point O, and the z axis is perpendicular to the x and y coordinate plane in the direction of increasing height.

The values of Vr, D, β, ε found (during primary ES processing) for each aircraft are transferred to secondary ES processing.

In the process of secondary processing of the digitized echo signals in the device 7, identification of coordinate points (Vr, D, β, ε) is carried out, binding to them in the corresponding bits of their digital sequences of identification addresses and signals of a single time. Next, according to the results of inter-period measurements (with a fixed time step) of the coordinate points, the trajectory and heading speed V _{to the} movement of each aircraft are calculated.

The numerical value of the heading speed V _{to the} movement of the aircraft is determined from the expressions:

Where:

Vr, V _β - the radial speed of the aircraft and the speed of its movement in azimuth, respectively;

c is the speed of light;

F _D - Doppler frequency;

λ is the wavelength of the corresponding ES;

fi is the radiation frequency of the corresponding ES;

δβ is the increment of the coordinate value of the azimuth of the aircraft for the specified time interval Δt;

Δt is the sampling interval over the measurement time.

The trajectory parameters of the aircraft motion found in (9) are compared with the data bank of the parameters of typical aircraft and, based on the results of their coincidence, they decide on the recognition of a specific type of aircraft and their motion parameters.

или

производят перевод указанных рабочих частот на частоты, ближайшие по рангу их расположения в откорректированной полосе резонансных частот Δf_рзс, свободных от радиопомех.Periodically in the process of primary and secondary processing of echo signals, an analysis of the interference environment and adjustment of the ranked set of Δf _RZS frequencies for resonant sounding of aerodynamic and ballistic aircraft are carried out. When sighting or random active interference occurs at the current operating frequency

or

translate the specified operating frequencies into frequencies closest to the rank of their location in the adjusted band of resonant frequencies Δf _RZS , free from radio interference.

At the same time, the results of the trajectory processing of the signals are displayed on the monitor and transmitted (block 9) to the external user of radar information in the form of a digital radar data stream (RLD) on a single time scale.

The invention is not limited to the described example of its implementation. In the framework of the present invention, other variants of its implementation are possible, without going beyond the scope of the independent claims.

In particular, for a circular overview of airspace in a resonant station, several stationary antenna systems 1 located on the sides of a regular polygon can be used. For a simultaneous all-round view of the airspace, their transmitting and receiving devices can be spaced along the carrier frequency in the frequency domain of the optimal resonant sounding. The device 6 and 7 of the primary and secondary processing of resonant echo signals can be performed on the basis of industrial electronic computers (computers) with built-in programs for processing resonant echo signals and exchanging information between station elements and the external environment.

The invention was developed at the level of a prototype of a resonant radar station and antenna systems 1 for it in the meter range of electromagnetic waves. Tests of the prototype showed the achievement of the claimed technical result and the solution of the task. The industrial development of the station under the trademarks “Resonance-Η” and “Resonance-NE” is being prepared, depending on its specific elemental configuration.

Information sources

1. Structure resonant radar detection apparatus and method. US 4897660, 01/14/1986.

2. Nebabin V.G., Sergeev V.V. Methods and techniques of radar recognition. - M .: Radio and communications, 1984, p. 79, fig. 3-21.

3. Radar method for detecting stealth unmanned aerial vehicles. RU 2534217, 11.27.2014.

4. Theoretical foundations of radar. / Ed. POISON. Shirman. M .: Soviet Radio, 1970, 560 p.

5. Antenna support for the receiving phased antenna array of the Resonance radar. CJSC NIC RESONANCE. RU 154296, 07.23.2015.

6. Multi-pile foundation and method of its construction on frozen soils. CJSC NIC RESONANCE. RU 2015104077, 2016.

7. Support-spacer connecting element. RU 160098, ZAO Research Center Resonance. 2016.

8. Aerial support lift. LLC "IST". RU 2015152360, 2016.

Claims (50)

1. The method of resonant radar, including sounding the airspace of the probable location of aircraft (LA) by pulsed electromagnetic radiation in the frequency range of resonant reflections from the aircraft, receiving the reflected resonant echo signals, converting them into digital form, primary and secondary processing of digitized echo signals, characterized in that Before the start of sounding, the optimal range Δf _{opt of the} resonant sounding frequencies is selected, in which the search for frequencies free of ac interference, ranking them in order of priority according to the proximity of frequencies to the central frequency of the optimal range of resonant frequencies and forming a ranked set of Δf _pcc frequencies for resonant detection of aerodynamic and ballistic aircraft, in the ranked frequency band, two operating frequencies spaced apart in frequency are selected in priority order

and

soundings sufficient for simultaneous detection of aerodynamic and ballistic aircraft simultaneously over the entire sector of the airspace survey, at one of the selected frequencies a long sounding signal (ZS1) is formed with a reduced divergence in the horizontal plane for detecting aircraft in the far zone of the field of view, at a different frequency - short probing signal (ЗС2) of increased divergence for detecting and resolving response signals from aircraft in range in the near zone of the field of view, formed probing signals the channels modulate in frequency according to a linear law and sequentially emit them with a repetition period T simultaneously across the entire field of view of the airspace in the form of a plurality of spade-shaped linear-frequency-modulated (LFM) radio beams, in each sounding period T initially emit a long (τ1) LFM signal ЗС1 and then with a delay of τ _ass - short (τ2) LFM signal ZS2, after radiation chirp signals during a time radiosilence AP transmitters in each period T reception produce resonant chirped echo (ES) reflected from LA odnov TERM around the field of view of the airspace receiving azimuth and elevation channels, in the process of receiving the reflected echo signals received resonance signals into each receiving channel are separated in frequency

and

for parallel processing of short and long LFM ES, they are amplified, transferred to an intermediate frequency and digitized, during the conversion of signals into digital form, the digitized streams of the LFM ES are converted into a floating point representation format, during the initial processing, the digitized LFM ES are subjected to quadrature processing to reduce the polarization energy loss of the received signals, compress them by intrapulse LFM processing to increase the resolution of the marks from the aircraft in range, measure the range D to LA by means of a stepwise shift in range and mutual correlation processing of the probing and received signals and by recording the range to LA by the moment of the maximum of the correlation function, simultaneously measure the angular coordinates of the aircraft in azimuth β and elevation angle ε by stepwise phase shift and correlation processing of the amplitude-phase distribution of signals in the azimuthal and elevation reception channels and by recording the angular direction on the aircraft to the maximum of the mutual correlation function in the corresponding angular directions x, in parallel, they carry out inter-period coherent accumulation of the processed signals, rejection of passive interference and threshold processing of signals to isolate signals from the aircraft against the background of interference, signals from the aircraft that have passed threshold processing are filtered by the Doppler frequency and the radial (Vr) speed of the aircraft is determined by the Doppler frequency, corresponding to the maximum value of the signal amplitude, the found values of Vr, D, β, ε for each aircraft in the form of multi-digit sequences of digital signals are transmitted for secondary processing, and in the secondary the processing of the digitized echo signals carries out their identification, reference to the aircraft signals in the corresponding bits of their digital sequences of identification addresses and signals of uniform time, the trajectory and the heading speed V _{to the} movement of each aircraft are calculated, the found motion parameters of the aircraft are compared with the data bank of parameters of typical aircraft and according to their results coincidences decide on the recognition of a specific type of aircraft and their motion parameters, the results are displayed by the processing path on the monitor and on a single the belts transmit to the external user the radar information in the form of a digital radar data stream (RLD). 2. The method according to p. 1, characterized in that the optimal value of the frequency range Δf _{opt of the} resonant radar is selected from the minimum time for a frequency review of the selected sector of space for the simultaneous detection of aerodynamic and ballistic aircraft with a resonant effective scattering surface (EPR) of at least square units meters. 3. The method according to p. 2, characterized in that the optimal value of the frequency range Δf _{opt of the} resonant radar is selected from the condition of the minimum size of the intersection of the areas of resonant reflections at the EPR level of at least 3 m:

Where:

- intersection of frequency domains

all I types of aircraft;

- resonant frequency band of the i-th type of aircraft; - σi is the minimum allowable resonance value of the EPR for the detection of the i-th type of aircraft; - i, I - the current and maximum value of the types of serviced aircraft, respectively. 4. The method according to p. 1, characterized in that the formation of a ranked set of Δf _pcc frequencies for resonance sensing of aerodynamic and ballistic aircraft is selected from the condition

j = 1 ... J, n = 1 ... N, Where: Δf _n is the current value of the resonant frequencies occupied by active interference;

- j-th frequency of the probing signals, free from interference at the current time; f _n - n-th interference frequency in the optimal band of resonant frequencies Δf _opt ; j, J is the current number of the frequency rank, characterizing the degree of proximity of its proximity to the center Δf _opt , and the total number of ranks, respectively; n, N is the current interference frequency number and the total number of interference frequencies in the resonant frequency band Δf _opt . 5. The method according to p. 1, characterized in that the period T of the probing LFM signals and the duration of the first probing LFM signal ЗС1 are selected from the condition for detecting the aircraft at the maximum range D _{max with a} long (τ1) probe signal with a narrow Δεy in its elevation plane plane diagram directivity:

Where: c = 3 × 10 ⁸ km / s is the propagation velocity of electromagnetic waves; Рзс1 - power density of the first (ЗС1) sounding LFM pulse; Δεy, Δβ is the total scattering angle of radiation ZS1 in the resonant EMW range in the elevation and azimuthal plane, respectively; σ = 3 m - the minimum size of the EPR at resonant reflection of ZS1; Emin = 10 ^-13 J / cm ² - the sensitivity of the receiving devices. 6. The method according to p. 1, characterized in that the duration τ2 of the second probing LFM signal ЗС2 and its time delay Δτ relative to ЗС1 are selected from the conditions for the possibility of resolving the echo signals in range and separate Δr _{min for} observing the aircraft in each angular direction: τ2≤Δr _min / s, Δτ≥t _per; Where: t _per - the duration of the transient processes in the transmitting path after the radiation of the first ZS1. 7. The method according to p. 1, characterized in that the exchange rate V _{to the} movement of the aircraft is determined from the expressions:

Where: Vr, V _β - the radial speed of the aircraft and the speed of its movement in azimuth, respectively; c is the speed of light; F _D - Doppler frequency; λ is the wavelength of the corresponding GL; f0 is the radiation frequency of the corresponding ES; δβ is the increment of the coordinate value of the azimuth of the aircraft for the specified time interval Δt; Δt is the sampling interval over the measurement time. 8. The method according to p. 1, characterized in that in the process of measuring the coordinates of the aircraft, a topocentric coordinate system is used, in which the center of coordinates is located at point O near the Earth's surface with geodetic coordinates B - latitude, L - longitude, H - height, x axis and y which are located in a plane parallel to the tangent plane to the surface of the Krasovsky ellipsoid passing through point O, and the z axis is perpendicular to the x and y coordinate plane in the direction of increasing height. 9. The method according to p. 1, characterized in that periodically during the primary and secondary processing of the echo signals an analysis of the interference situation and adjustment of the ranked set of Δf _pcc frequencies for resonant sounding of aerodynamic and ballistic aircraft are carried out. 10. The method according to p. 9, characterized in that when the sighting or random active interference at the current operating frequency

or

translate the specified operating frequencies into frequencies closest to the rank of their location in the adjusted band of resonant frequencies Δf _pcc free of radio interference. 11. A resonant radar station, characterized in that it contains at least one transmitting and at least two receiving azimuth and elevation antenna-feeder devices (AFUs) mounted on the antenna mounts for multipath sounding of airspace at the resonance frequencies of aircraft (LA) and reception at these frequencies of reflected resonant echo and radio interference signals, the input of the transmitting AFU through a multi-channel power amplifier is connected to the output of a two-frequency linear-frequency generator o-modulated (LFM) probing signals (LF) of increased and short duration with the possibility of tuning the carrier frequency in the resonance frequency range of aerodynamic and ballistic aircraft, the signal outputs of the receiving AFUs are connected to the inputs of the receiving superheterodyne devices, the reference inputs of which are connected to the output of the two-frequency generator of the ZS, and the signal outputs - through the device of analog-to-digital conversion and quadrature demodulation of ES and through devices of primary and secondary processing of ES - with automated m workstation (AWS) of the station operator, whose signal and control outputs are connected through the bi-directional active interface bus to the control inputs of the ES generator, primary and secondary processing of resonant ES devices, and through the equipment for receiving / transmitting data (ADF) to external consumers of radar information. 12. The station according to claim 11, characterized in that the device for analog-to-digital conversion and quadrature demodulation of the ES contains a series-connected analog-to-digital converter (ADC), a quadrature demodulator (CD) and a transmission unit of digitized ES. 13. The station according to claim 11, characterized in that the primary processing unit of the echo signals is capable of parallel processing of the digitized ES from the azimuthal and elevation AFUs and contains azimuthal and elevation primary processing channels connected through a block of digital diagram formation by elevation and coordinate point generation block Aircraft with the output of the primary processing unit ES, and the azimuthal channel of the primary processing ES contains series-connected reception unit of digitized ES with AFU 1.2, the block intrapulse processing and compression of the chirp ES, digital azimuth block diagram, coherent accumulation block, passive interference rejection block in azimuth and range, detector, threshold processing unit, signal marking unit and side lobe suppression unit in range and azimuth, and angular primary processing channel - series-connected unit for the reception of digitized ES with orthogonal polarization from the AFU, a circuit for recovering the amplitude and polarization of the ES, including two filters and an adder, an intrapulse processing unit ki and chirped ES compression and coherent accumulation block. 14. The station according to claim 12, characterized in that the primary processing unit of the echo signals is made of modular design on programmable logic integrated circuits (FPGA) with reprogrammable memory and additionally contains a central control and data transmission processor connected by interface lines, a master and slave digital processing unit long and short ES, synchronizer and input-output device. 15. The station according to claim 1, characterized in that the secondary processing unit of the echo signals is made according to the standard scheme of an industrial electronic computer using two coreless i7 computers and two expanders - mezzanines of the 4 × 1 Gbit Ethernet and 4 × RS422 series with a programmable block Gard and Flesh memory. 16. The station according to claim 1, characterized in that the antenna mount is quickly erected and resistant to wind loads and seasonal soil movement and contains at least one load-bearing mast mounted on metal beams — a linear grill that combines the upper ends of metal screw piles, each of which it is made in the form of a pipe with an insulating non-freezing coating based on a polymer and a screw working element fixed to its lower end for rigidly fastening the lower end of the pile in hard soil below the level of its season th thawing.

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