RU2171483C1 - Gravitation-wave detector - Google Patents

Abstract

FIELD: gravitation-wave astronomy, detection of gravitation-wave signals from binary relativistic astrophysical objects. SUBSTANCE: multichannel reception with real time detection is provided due to employment of circuit of correlation-filtration processing of legitimate signals with use of signals formed in gravitation-wave detector as reference signals in response to gravitation-wave action. EFFECT: real time multichannel simultaneous detection of gravitation-wave signals from many sources. 1 dwg

Description

 The invention relates to laser-interferometric gravitational-wave (GW) detectors and can be used, for example, in gravitational-wave astronomy to detect periodic low-frequency gravitational-wave signals from double relativistic astrophysical objects.

 It is known that there are theoretical predictions about the formation of the elastodynamic response of solid-state GW antennas - Weber type detectors [1], the electrodynamic response of long-base Michelson type laser interferometric antennas [1] and compact [2] laser interferometric antennas to the effect of the gravitational radiation field (GI ) Weber-type GW antennas and long-base laser interferometric antennas are designed to detect short pulsed GW signals from flash sources, the spatio-temporal characteristics of which are unknown. This reduces the reliability of the detection of GV signals, since the required instantaneous signal-to-noise ratio for reliable detection of the GV signal from a flash source of GI by such detectors should be more than unity.

 Known [3] a GW detector for detecting periodic low-frequency GW signals from binary astrophysical objects, which is closest to the claimed object and therefore is selected as a prototype. It is a laser with two spatially nonequivalent traveling-wave optical resonators built on the same reflective elements, and contains an active element and a working medium in it, the first, second, and third deaf hologram diffraction reflectors, a deaf reflector with a piezoelectric element on its back side , a translucent mirror with a thin diffraction grating on its reverse side, a phase modulator, first, second, third and fourth polarizing prisms, a polarizer, the first translucent d Call duration mirror, the first photodetector unit with frequency-locked at its output, a second photodetector unit with a phase locked at its output, a third photodetector vnutriperiodny accumulation comb filter, a first multiplier with a first correlator at the output of the second correlator to a second multiplier at its output. The active element, a semitransparent mirror with a diffraction grating on the back side, the first blind hologram diffraction reflector, phase modulator, the first polarizing prism, the second blind hologram diffraction reflector, the second polarizing prism, the translucent mirror with the diffraction grating on the back side, placed in series on the path of optical radiation, the third blind hologram diffraction reflector, a blind reflector with a piezoelectric element on the reverse side form the first optical s traveling wave resonator. Active element, a blank reflector with a piezoelectric element on the back side, a third blank hologram hologram diffraction reflector, a fourth polarizing prism, a second blank hologram hologram diffraction reflector, a third polarizing prism, a blank reflector with a piezoelectric element on the back side, the first blank hologram reflective diffraction diffraction mirror a lattice on the reverse side forms a second traveling-wave optical resonator. The first, second, and third deaf hologram diffraction reflectors, a deaf reflector with a piezoelectric element on the reverse side, a translucent mirror with a thin diffraction grating on the reverse side are located on the vertices of a regular pentagon. The transmission planes of the first and second polarizing prisms are orthogonal to the transmission planes of the third and fourth polarizing prisms. The output of a semitransparent mirror with a thin diffraction grating on the reverse side through the polarizer and the first fission semitransparent mirror is optically coupled to the input of the first photodetector. The output of the frequency-locked loop is connected to the controlled input of the piezoelectric element of the deaf reflector, and the output of the phase locked loop is connected to the controlled input of the phase modulator. The optical radiation of the first and second optical resonators of the traveling waves through a translucent mirror with a thin diffraction grating on the back side comes out of these resonators on mutually orthogonal linear polarizations. The output optical radiation after passing through the polarizer get the opportunity to form interference fields at the inputs of the photodetectors. Photodetectors are designed to detect changes in the interference field resulting from changes in the phase difference in the optical radiation of the resonators, which in turn occurs as a result of the GW action of the detected periodic low-frequency GW signal.

 The principle of operation of such a GW detector is that as a result of the GW action of a detected periodic low-frequency GW signal on the optical radiation of the first and second optical traveling-wave resonators, a phase incursion occurs in optical radiation according to the law through a change in their refractive indices along the optical propagation paths of radiation changes in the GV signal. Due to the geometric nonequivalence of the first and second resonators, this effect leads to various changes in the refractive indices along the optical propagation paths of radiation and, consequently, to different phase incursions in these optical radiation. By the presence, magnitude and law of variation of the phase difference difference in the optical radiation of the resonators, the effect of the GW signal on the optical radiation of the resonators is judged, and therefore the presence (detection) of the detected GW signal. Thus, the known prototype device [3] has the fundamental possibility of detecting periodic low-frequency GW signals from double relativistic astrophysical objects.

 However, the prototype has a significant drawback - single-channel detection of GV signals (i.e., the ability to simultaneously detect only one source of GI). In addition, even after ensuring the necessary signal-to-noise ratio (for example, a long inter-period accumulation of the detected HV signal against the background of interference), the possibility of operating in the current time scale is excluded. This, in turn, excludes the possibility of aperture synthesis of the radiation pattern — the response of the GW detector to the action of the GW signal when the Earth moves in orbit, which is necessary to determine (identify) the angular coordinates of the GI.

 The problem to which the invention is directed is to develop a gravitational-wave detector that provides multichannel simultaneous detection (reception, detection) of GW signals from many sources of GI in the current time scale.

 The essence of the invention lies in the fact that in the known gravitational-wave detector containing the active element and the working medium in it, the first, second and third deaf hologram diffraction reflectors, a deaf reflector with a piezoelectric element on its back side, a translucent mirror with a thin diffraction grating on it reverse side, phase modulator, first, second, third and fourth polarizing prisms, polarizer, first translucent dividing mirror, first photodetector with a frequency-locked loop and at its output, a second photodetector with a phase-locked loop at its output, a third photodetector, an inter-period comb accumulation filter, a first correlator with a first multiplier at its output, a second correlator with a second multiplier at its output, while the first, second, and third deaf hologram diffraction reflectors, a dull reflector with a piezoelectric element on the back side, a translucent mirror with a thin diffraction grating on the back side are placed on the vertices of a regular pentagon, and the output is translucent o mirrors with a thin diffraction grating on the back side through the polarizer and the first dividing translucent mirror are optically connected to the input of the first photodetector, while the output of the frequency-locked loop is connected to the controlled input of the piezoelectric element of the deaf reflector, and the output of the phase-locked loop is connected to the controlled input of the phase modulator - for the solution of the problem - a second translucent dividing mirror, a subtraction scheme, an adder of the interference channel, an adder of a correlation autocomp are introduced a signal carrier, a key circuit, a response signal simulator phase shifting to π / 2, a signal extraction circuit with a threshold circuit at its output, the output of the first translucent dividing mirror through the second translucent dividing mirror connected to the input of the second and third photodetectors, and the output of the last connected in parallel to one of the inputs of the subtraction circuit directly, and through the adder of the interference channel is connected to the second input of the subtraction circuit, the output of which is connected to the input of the intra-period comb filter In addition, the output of the third photodetector is connected to the main input of the adder of the correlation auto-compensator of the signal, to the auxiliary inputs of which the outputs of the first and second multipliers are connected, the outputs of which are also connected in parallel to the inputs of the signal extraction circuit and to the inputs of the key circuit, the outputs of which are connected to the inputs the adder of the interference channel, while the controlled input of the key circuit is connected to the output of the threshold circuit, in addition, the output of the response signal simulator with the input of the first multiplier and with one of the outputs of the first correlator is connected directly to the input of a second multiplier and to the first input of the second correlator is connected via a phase shift at π / 2 circuit, to the second inputs of said first and second correlators connected to the output signal of the adder correlation automatic compensator.

 Introduction of new elements: a second translucent mirror, a subtraction circuit, an adder, an interference channel, an adder of an auto-compensator (AK) signal, a key circuit, a simulator of the response signal of a GV detector to the action of a GV signal, phase shifting to π / 2 circuits, a signal extraction circuit with a threshold the circuit at its output, their relative position both in relation to each other and in relation to known elements of the device, optical and electrical connections between them and elements of the known device allow the filtering process of the useful signal It is possible to deduce from the resonators that, in turn, due to the possibility of duplication of the introduced new elements (with the corresponding optical and electrical connections) in terms of the number of detected HV signals, it will be possible to achieve the solution of the problem posed — providing multi-channel detection (reception, detection) of HV signals from many GI sources with the required signal to noise ratio.

 In contrast to the known technical solution of the prototype, where due to the introduction of the correlation negative feedback and the correlation positive feedback of another resonator into the optical paths of one resonator, adaptive inter-period accumulation of the GW signal from one GI source is provided, in the claimed invention the filtering process of the useful signal is derived from resonators. To this end, an “interference + signal” channel and an “interference” channel are formed at the output of the third photodetector, from which the detected GW signal is subtracted. "The latter is generated in the correlators of auxiliary quadrature channels — an auto-compensator for the signal correlation function from the output of the simulator of the response of the GV detector to the influence of GV -signal and from the output of the auto-compensator adder, the main input of which receives a signal from the output of the third photodetector. A signal allocation circuit with a threshold circuit at its output, to the inputs of which a signal The outputs from the auxiliary quadrature channels of the auto-compensator (parallel to the inputs of the adder of the interference channel and the auto-compensator adder) together with the threshold circuit generates a signal (according to the useful component) by the criterion "yes" - "no" to control the key circuit. If the specified detection threshold is exceeded with an acceptable probability correct detection and false alarm by the output signal (monotonously increasing with increasing averaging time in the correlators) of the threshold circuit through the key circuit, the auxiliary outputs AK channels connected to the second inputs of the combiner channel interference.

 This provides the subtraction of the detected HV signal from the signal from the third photodetector in the adder of the "interference" channel. Therefore, in the subtraction scheme, combining the channels "interference + signal" and "interference", the interference signal is compensated. As will be shown below, the signal-to-noise ratio at the output of the subtraction circuit will be approximately unity. In the intra-period comb accumulation filter, where a signal is received from the output of the subtraction circuit, during the half-period of accumulation of the latter, the required signal-to-noise ratio in the current time scale is reached.

 The optical-functional diagram of the claimed object is presented in the drawing, where it is indicated: 1 - a blank reflector with a piezoelectric element on its reverse side; 2 - the active element and the working environment in it; 3 - translucent mirror with a thin diffraction grating on its reverse side; 4, 8, 11 - the first, second and third deaf hologram diffraction reflectors, respectively; 5 - phase modulator; 6, 7, 9, 10 - the first, second, third and fourth polarizing prisms, respectively; 13, 16, 19 - second, first and third photodetectors, respectively; 14 - polarizer; 15, 18 - the first and second translucent dividing mirrors, respectively; 12, 17 — phase and frequency auto-tuning blocks, respectively; 20 - intra-period comb accumulation filter; 21 is a subtraction scheme; 22, 32 - adders of the interference channel and the correlation signal self-equalizer, respectively; 23 is a key diagram; 24 is a threshold circuit; 25 is a signal allocation circuit; 26 - simulator response signal; 27, 30 - the first and second multipliers, respectively; 28, 31 - the first and second correlators, respectively; 29 - phase-shifting circuit on π / 2.

 A deaf reflector 1 with a piezoelectric element on its reverse side, a translucent mirror 3 with a thin diffraction grating on its reverse side, the first 4, second 8 and third 11 deaf hologram reflectors are located at the vertices of a regular pentagon. The active element 2 with a working medium in it, which serves to generate laser radiation, is located between the deaf reflector 1 and the translucent mirror 3. Active element 2, the translucent mirror 3, the first deaf reflector 4, the second deaf reflector 8, the translucent mirror 3, the third deaf reflector 11, a blank reflector 1, an active element 2 form a first traveling-wave optical resonator. The active element 2, the blank reflector 1, the third blank reflector 11, the second blank reflector 8, the blank reflector 1, the first blank reflector 4, the translucent mirror 3, the active element 2 form a second traveling wave resonator. Elements 1, 2, 3, 4, 8, 11 are common to the first and second resonators. On the path of the optical radiation of the first resonator between the first 4 and second 8 blank reflectors, a phase modulator 5 and a first polarizing prism 6 are arranged in series, between the second 8 blank reflector and a translucent mirror 3 there is a second polarizing prism 7, and between the blank reflector 1 and the second blank reflector 8 between the second blank reflector 8 and the third blank reflector 11 are placed the third 9 and fourth 10 polarizing prisms, respectively. The output of the translucent mirror 3 with a thin diffraction grating on its reverse side (optical output of the resonators) through the polarizer 14 and the first translucent mirror 15 is optically coupled to the input of the first photodetector 16. The output of the polarizer 14 is through the first fission translucent mirror 15, the second fission mirror 18 is optically coupled in parallel also with the inputs of the second 13 and third 19 photodetectors. The output of the first photodetector 16 through the frequency-locked loop 17 is connected to the controlled input of the piezoelectric element mounted on the back of the deaf reflector 1. The output of the second photodetector 13 through the phase locked loop 12 is connected to the controlled input of the phase modulator 5. The output of the third photodetector 19 is directly and parallel through the channel adder interference 22 is connected to the inputs of the subtraction circuit 21, the output of which is connected to the input of the intra-period comb filter of accumulation of 20 GV signals. The output of the third photodetector 19 is also connected in parallel with the main input of the adder 32 of the correlation auto-compensator. The output of the response signal simulator 26 is connected in parallel with the input of the first multiplier 27 and one of the inputs of the first correlator 28, and through the phase shifting circuit on π / 2, the circuit 29 is connected in parallel with the input of the second multiplier 30 and with one of the inputs of the second correlator 31. The second inputs of the correlators 28 and 31 are connected to the output of the adder 32. The outputs of the multipliers 27 and 30 are connected in parallel with the auxiliary inputs of the adder of the auto-compensator 32, through the key circuit 23 with the second inputs of the adder of the interference channel 22, and are also combined with the inputs of the allocation circuit with Ignal 25 (scheme for calculating the correlation integral according to [4]). The output of the signal extraction circuit 25 through the threshold circuit 24 is connected to the controlled input of the key circuit 23. The outputs of the device are the output of the threshold circuit 24 (by the criterion “yes” - “no” - signal detection) and the output of the comb filter accumulation 20 (estimation of signal parameters).

 The device operates as follows.

Optical radiation with a full set of polarizations, coming out of the active element 2, is reflected from a translucent mirror 3 with a thin diffraction grating on its reverse side, hits the first hologram diffraction reflector 4, which separates the optical radiation by polarization and directs part of it with TM polarization at an angle incidence equal to the angle of reflection through the phase modulator 5 and the first polarizing prism 6 to the second hologram diffraction reflector 8, which then directs it at an angle not equal to the angle reflection through the second polarizing prism 7 to the translucent mirror 3, after which the radiation with TM polarization falls on the third hologram diffraction reflector 11, which returns it at an angle of incidence not equal to the angle of reflection, through the dull reflector 1 to the active medium 2. Thus, optical radiation with TM polarization is generated in the first resonator formed sequentially from elements 2, 3, 4, 5, 6, 8, 7, 3, 11, 1. Another part of the radiation with TE polarization orthogonal to the TM polarization, reflected from the hologram of the diffraction reflector 4, the floor with an angle not equal to the angle of reflection hits the blind reflector 1, which directs it through the third polarizing prism 9 to the second hologram reflector 8, after which the radiation with TE polarization is directed at an incidence angle not equal to the angle of reflection, through the fourth polarizing a prism 10 to the third hologram reflector 11, which reflects it at an angle equal to the angle of incidence, towards the blank reflector 1, after which optical radiation with TE polarization returns to active element 2. Thus, optical radiation with TE polarization is generated in the second resonator formed sequentially from elements 2, 3, 4, 1, 9, 8, 10, 11, 1. Polarization prisms 6, 7 and 9, 10 are passed further through radiation only, respectively, with TM and TE polarizations, thus cleaning out the optical radiation in the first and second resonators, respectively, from radiation with irregular polarization. At unequal lasing frequencies in the first and second resonators, optical radiation with TE and TM polarizations can circulate in the respective resonators in both directions. At equal generation frequencies, the generation mode is stable, in which radiation with TE and TM polarizations inside the active element 2 propagate towards each other (as shown by arrows in the drawing). To output optical radiation from the resonators, a translucent mirror 3 is used with a thin diffraction grating on its reverse side, which ensures the combination of optical fluxes with TE and TM polarizations. After passing through the polarizer 14, in which the plane of transmission of linearly polarized light is at an angle of 45 ^o with the plane of the optical resonators, an interference field is formed which, through the translucent dividing mirrors 15 and 18, is incident on the photodetectors 16, 13 and 19. From the photodetector 16, the output voltage is supplied to the unit auto-tuning 17, which generates an error signal for the piezoelectric element mounted on the mirror 1, and equalizes the generation frequency in the first (ω ₁ ) and second (ω ₂ ) resonators, i.e. leads to the establishment of a mode of synchronization of radiation in the resonators. The output voltage from the photodetector 13 enters the phase-locked loop 12, which generates an error signal for the phase modulator 5, and ensures stabilization of the phase difference of the optical radiation of the first and second resonators at a level exceeding the useful signal by at least two orders of magnitude.

где Φ_1g(t),Φ_2g(t) - составляющие, обусловленные гравитационно-волновым воздействием детектируемого ГВ-сигнала на оптическое излучение первого и второго резонаторов через изменения их показателей преломления вдоль оптических путей (сигнал-отклик ГВ-детектора на ГВ-сигнал); Φ_1gni(t),Φ_2gni(t) - составляющие, обусловленные тем же видом воздействия - ГВ-сигналов от других мешающих периодических ГВ-источников; Φ_1зnj(t),Φ_2зnj(t) - составляющие, обусловленные всеми видами помеховых механических воздействий на отражатели 1, 3, 4, 8, 11 (вибрационные, сейсмические, акустические, тепловые); Φ_1n(t),Φ_2n(t) - составляющие, обусловленные техническими и естественными флуктуациями фазы в активной среде. При работе внутри зоны синхронизации (ω₁= ω₂) в результате ГВ-воздействия на оптические излучения первого и второго резонаторов возникает разность фаз встречных волн, равная

где

- амплитуда модуляции фазы, откуда k_ГВД = 0,951 - коэффициент отклика (детектирования) ГВ-детектора на воздействие поля ГИ, обусловленный данной геометрической конфигурацией резонаторов (рассчитывается по методике, изложенной в [5]);
h,ω_g,Φ₀ - безразмерная амплитуда, частота и случайная начальная фаза детектируемого ГВ-сигнала;
Φ₁= arctg(ω_g/Δω_з) - сдвиг фазы ГВ-сигнала в лазерной системе;
ω₀ - частота оптического излучения;
Δω_з - ширина полосы синхронизации (ширина зоны захвата).It was shown in [3] that the phase shifts Φ ₁ (t) and Φ ₂ (t) in the optical radiation of the first and second resonators can be represented as

where Φ _1g (t), Φ _2g (t) are the components due to the gravitational-wave action of the detected GV signal on the optical radiation of the first and second resonators through changes in their refractive indices along the optical paths (signal-response of the GV detector to the GV signal ); Φ _1gni (t), Φ _2gni (t) - components caused by the same type of influence - GW signals from other interfering periodic GW sources; Φ _1зnj (t), Φ _2зnj (t) - components caused by all types of interfering mechanical effects on the reflectors 1, 3, 4, 8, 11 (vibrational, seismic, acoustic, thermal); Φ _1n (t), Φ _2n (t) are the components due to technical and natural phase fluctuations in the active medium. When working inside the synchronization zone (ω ₁ = ω ₂ ) as a result of the GW action on the optical radiation of the first and second resonators, a phase difference of counterpropagating waves arises, equal to

Where

- phase modulation amplitude, from where k _GVD = 0.951 - response coefficient (detection) of the GV detector to the influence of the GI field, due to this geometric configuration of the resonators (calculated by the method described in [5]);
h, ω _g , Φ ₀ — dimensionless amplitude, frequency, and random initial phase of the detected GW signal;
Φ ₁ = arctan (ω _g / Δω _h ) is the phase shift of the GW signal in the laser system;
ω ₀ is the frequency of optical radiation;
Δω _z - the width of the synchronization band (the width of the capture zone).

With a synchronization band equal to 1 Hz, h = 10 ^-22 , ω _g ≅ 1 MHz, ω ₀ = 10 ¹⁵ Hz, we have ΔΦ _12g = 10 ^-7 rad.

- составляющая полезного сигнала (сигнала отклика ГВ-детектора), обусловленная разностью фаз Φ_1g(t)-Φ_2g(t) = ΔΦ_12g(t) (см. формулы (1)-(3));

- составляющая, обусловленная суммой соответствующих разностей фаз от всех видов помех, указанных в (1) и (2). Здесь и далее предполагается (для простоты), что коэффициент передачи фотодетектора равен единице, и выходной сигнал его безразмерен.After the synchronization mode of the radiation in the resonators is established using the frequency auto-tuning unit 17, the output voltage of the photodetector 19 is described by the expression (dimensionless voltages are considered below)
V ₁₂ (t) = V _12g (t) + V _12n (t), (4)
Where

- component of the useful signal (response signal of the GW detector), due to the phase difference Φ _1g (t) -Φ _2g (t) = ΔΦ _12g (t) (see formulas (1) - (3));

- component due to the sum of the corresponding phase differences from all types of interference specified in (1) and (2). Hereinafter, it is assumed (for simplicity) that the transmission coefficient of the photodetector is unity, and its output signal is dimensionless.

. Нарушение этого условия приводит либо к искажению

, либо к его компенсации. Уровню

на выходе фотодетектора 19 будет соответствовать

. С выхода фотодетектора 19 аддитивная смесь детектируемого ГВ-сигнала V_12g(t) и помехового сигнала V_12n(t) поступает на основной вход сумматора 32. Поскольку начальная фаза Φ₀ ГВ-сигнала априори неизвестна, то для исключения фактора неизвестности начальной фазы Φ₀ автокомпенсатор содержит два вспомогательных квадратурных канала. С выхода имитатора 26 сигнал-отклик V_ug(t) = Ucosω_gt на частоте

(T_g - период детектируемого ГВ-сигнала) с единичной амплитудой U после перемножения на коэффициент βk(t) в умножителе 27 поступает на вспомогательный вход сумматора 32. Этот же сигнал после сдвига в фазовращателе 29 на

(т. е. квадратурная составляющая) и перемножения на квадратурный коэффициент β_⊥k_⊥(t) в умножителе 30 поступает на другой вспомогательный вход сумматора 32. Выходное напряжение V_Σ(t) сумматора 32 равно [4]:

где βk(t) и β_⊥k_⊥(t) - напряжения регулирования (коэффициенты передач), формируемые в корреляторах 28 и 31, соответственно;
β ≫ 1, β_⊥≫ 1 - коэффициенты усиления в цепи корреляционной отрицательной обратной связи;
черта сверху означает усреднение по времени на интервале MT_g=MNΔt;
Δt - шаг отсчета (не менее, чем время корреляции фазового шума, определяющего величину V_12n(t)), N - количество отсчетов за период Т_g, М - число периодов.Experimental studies have shown [6] that, if there is a component of the useful signal in the error signal, the phase difference stabilization system should have a stabilization threshold exceeding by at least two orders of magnitude the phase difference due to the action of the useful signal, i.e.

. Violation of this condition leads to either a distortion

, or to his compensation. Level

the output of the photodetector 19 will correspond

. From the output of the photodetector 19, the additive mixture of the detected GV signal V _12g (t) and the interfering signal V _12n (t) is fed to the main input of the adder 32. Since the initial phase Φ _{0 of the} GV signal is a priori unknown, to exclude the unknown factor of the initial phase Φ ₀ The auto-compensator contains two auxiliary quadrature channels. From the output of the simulator 26, the signal-response V _ug (t) = Ucosω _g t at a frequency

(T _g is the period of the detected HV signal) with a unit amplitude U after multiplying by the coefficient βk (t) in the multiplier 27 is supplied to the auxiliary input of the adder 32. The same signal after a shift in the phase shifter 29 by

(ie, the quadrature component) and multiplication by the quadrature coefficient β _⊥ k _⊥ (t) in the multiplier 30 is fed to another auxiliary input of the adder 32. The output voltage V _Σ (t) of the adder 32 is [4]:

where βk (t) and β _⊥ k _⊥ (t) are the regulation voltages (gear ratios) generated in the correlators 28 and 31, respectively;
β ≫ 1, β _⊥ ≫ 1 - gain in the correlation negative feedback circuit;
the bar above means time averaging over the interval MT _g = MNΔt;
Δt is the sampling step (not less than the correlation time of the phase noise determining the value of V _12n (t)), N is the number of samples for the period T _g , M is the number of periods.

в полосе частот от нуля до 10 Гц [7] (амплитуда широкополосной помехи V_12n = ΔΦ_12n ≈ 3•10^-4 рад при уровне сигнала V_12g=ΔΦ_12g=10^-7 рад), то в выражениях (3) и (4) при значениях

сек, N=2,8927•10⁵ для T_g=2,8927•10³ (PSR 1537+1155 [8]) и М=900 имеем

где СКО - среднеквадратическое отклонение.Since after the operation of the phase locked loop 12, the spectral density of the phase noise amplitude will not exceed 10 ^-4 rad /

in the frequency band from zero to 10 Hz [7] (the amplitude of the broadband interference V _12n = ΔΦ _12n ≈ 3 • 10 ^-4 rad at a signal level V _12g = ΔΦ _12g = 10 ^-7 rad), then in expressions (3) and ( 4) with values

sec, N = 2.8927 • 10 ⁵ for T _g = 2.8927 • 10 ³ (PSR 1537 + 1155 [8]) and M = 900 we have

where the standard deviation is the standard deviation.

Then the output voltage of the adder 32 will be equal to
V _Σ (t) = V _12n (t) + Δ _n + Δ _c ,
where Δ _n ≈ 4 • 10 ^-8 and Δ _c are the component of the interference signals, due to the finite averaging time in the correlators 28 and 31, and the uncompensated residues of the useful signal at the output of the adder 32.

Точное знание (не менее, чем до четвертого знака) периода T_g детектируемого ГВ-сигнала позволит имитировать сигнал-отклик ГВ-детектора на ГВ-сигнал с коэффициентом корреляции с детектируемым равным порядка ρ = 0,999 и более. Тогда γ = 500, а нескомпенсированный остаток на выходе сумматора канала помехи 22 будет составлять величину Δ_c≈ V_12g(t)/γ = 10^-7 рад/500 = 2•10^-10 рад.Moreover, the suppression coefficient γ of the correlated components in the output signal V _Σ (t) of the adder 32 is determined by the correlation coefficient ρ between them and is equal to

Accurate knowledge (at least up to the fourth digit) of the period T _{g of the} detected GW signal will allow simulating the response signal of the GV detector to the GV signal with a correlation coefficient with a detectable one of the order of ρ = 0.999 or more. Then γ = 500, and the uncompensated balance at the output of the adder of the interference channel 22 will be Δ _c ≈ V _12g (t) / γ = 10 ^-7 rad / 500 = 2 • 10 ^-10 rad.

The voltages from the outputs of the auxiliary channels of the auto-compensator (outputs of the multipliers 27 and 30) equal to βk (t) V _ug (t) and β _⊥ k _⊥ (t) V _⊥ug (t), respectively, also pass through the key circuit 23 to the second interference channel adder inputs 22.

или с учетом (6)
V_nk(t) = V_12П(t)+Δ_n+Δ_c.The voltage V _PC (t) at the output of the adder 32 taking into account (4) is determined by the expression

or subject to (6)
V _nk (t) = V _12P (t) + Δ _n + Δ _c .

Thus, the interference component V _12n (t) (at the level of 3 • 10 ^-4 rad), the interference component due to the finite averaging time in the correlators (at the level of 4 • 10 ^-8 rad ) and uncompensated residues of the useful signal (at the level of 2 • 10 ^-10 rad).

The voltage V _CB (t) at the output of the subtraction circuit 21 will be equal
V _CB (t) = V ₁₂ (t) -V _nk (t) = V _12g (t) -Δ _n -Δ _c .

поступает на вход гребенчатого фильтра внутрипериодного накопления 20. Работа последнего обеспечивает через время, равное T_g/2, отношение сигнал/шум [5]

Поэтому для PSR 1537+1155, через время 900 T_g (время работы корреляторов 28 и 31) плюс T_g/2 (время внутриполупериодного накопления в 20) отношение сигнал/шум, равное ~ 1, на входе ГВ-системы возрастет на выходе 20 до величины ~ 50. При этом выходной сигнал V_вых(t) = V_12g(t) в дальнейшем будет присутствовать в текущем масштабе времени.Since V _12g (t) = 10 ^-7 rad is much larger than Δ _c = 10 ^-10 rad, the latter can be neglected, and then
V _CB (t) = V _12g (t) -Δ _n ,
which is equivalent to achieving a signal-to-noise ratio q _out equal to q _in - the ratio of the detected GV signal / (GV signal from other sources) at the input of the GV system. As already noted in [3], the ratio q _in does not exceed unity. Therefore, at the output of the subtraction circuit 21, the signal-to-noise ratio is established at a level approximately equal to unity. Next, the signal from the output of the subtraction circuit 21 s

arrives at the input of a comb filter of intra-period accumulation 20. The operation of the latter provides after a time equal to T _g / 2, the signal-to-noise ratio [5]

Therefore, for PSR 1537 + 1155, after a time of 900 T _g (operating time of correlators 28 and 31) plus T _g / 2 (half-time accumulation time of 20), the signal-to-noise ratio equal to ~ 1 at the input of the GV-system will increase at output 20 to a value of ~ 50. In this case, the output signal V _o (t) = V _12g (t) will continue to be present in the current time scale.

Напряжение Z в пороговом устройстве 24 сравнивается с пороговым значением Z₀, выставленным в соответствии с задаваемой вероятностью правильного обнаружения и ложной тревоги. При превышении порога Z₀ на выходе блока 24 появляется сигнал (критерий "да"). Этот же сигнал открывает ключевую схему 23 и только в этом случае напряжения с выходов умножителей 27 и 30 поступают на вторые входы сумматора канала помехи 22.The output voltages of the multipliers 27 and 30 z (t) = βk (t) V _ug (t) and z _⊥ (t) = β _⊥ k _⊥ (t) V _⊥ug (t) also go to the inputs of the signal isolation circuit 25, where calculates the correlation integral [4]

The voltage Z in the threshold device 24 is compared with a threshold value Z ₀ set in accordance with a given probability of correct detection and false alarm. If the threshold Z _{0 is} exceeded, a signal appears at the output of block 24 (criterion "yes"). The same signal opens the key circuit 23 and only in this case, the voltages from the outputs of the multipliers 27 and 30 are supplied to the second inputs of the adder of the interference channel 22.

Part of the inventive device, included at the output of the third photodetector 19, is repeated according to the number of detected HV signals, and the differences in the values of T _g are taken into account in the comb filter 20 and the simulator of the response signal 26. This allows multi-channel reception.

 Thus, the claimed device compares favorably with the prototype in that the elements introduced into it provide multichannel detection by the number of detected GW signals and the ability to detect a GW signal at a current time scale from a certain point in time, which in turn allows you to implement a synthesized antenna - GW - response when the Earth moves in orbit.

Sources of information
1. Milyukov VK, Rudenko VN. // Results of science and technology VINITI USSR Academy of Sciences, series Astronomy, 1991, v. 41, p. 147-193.

 2. Balakin A.B., Kisunko G.V., Murzakhanov Z.G., Rusyaev N.N. // DAN USSR, 1991, v. 316, No. 5, p. 1122-1125.

 3. Kaiqorodov V.R., Murzakhanov Z.G. // Gravitation & Cosmology, Moscow, Vol. 5, N1 (17), pp. 58-66 (1999) (Prototype).

 4. Theoretical foundations of radar. Under. ed. Shirmana Y.D. - M .: Owls. radio, 1970.

 5. Balakin A.V., Murzakhanov Z.G., Skochilov A.F. // Gravitation & Cosmology, Moscow, Vol. 3, N1 (9), pp. 71-81 (1997).

 6. Balakin A. B., Kisunko G. V., Murzakhanov Z. G., Skochilov A. F. et al. // Letters to the ZhTF, 1998, v. 24, No. 22, p. 86-92.

 7. Balakin A.B., Murzakhanov Z.G., Skochilov A.F. // Gravitation & Cosmology, Moscow, Vol. 5, N4 (20), 1999.

 8. G.H. Taylor, R.N. Manchester, A.G. Lyne.//Astrophysical Journal Supplement, 1993, v. 88, p. 529.

Claims (1)

 A gravity-wave detector containing an active element and a working medium in it, the first, second and third deaf hologram diffraction reflectors, a deaf reflector with a piezoelectric element on its reverse side, a translucent mirror with a thin diffraction grating on its reverse side, a phase modulator, the first, second , the third and fourth polarizing prisms, a polarizer, a first translucent dividing mirror, a first photodetector with a frequency-locked loop at its output, a second photodetector with a phase-locked block detuning at its output, a third photodetector, an intra-period comb accumulation filter, a first correlator with a first multiplier at its output, a second correlator with a second multiplier at its output, the first, second and third deaf hologram diffraction reflectors, a deaf reflector with a piezoelectric element at its inverse side, a translucent mirror with a thin diffraction grating on its reverse side is placed on the vertices of a regular pentagon, and the output of a semitransparent mirror with a thin diffraction grating on it the reverse side through the polarizer and the first dividing translucent mirror is optically connected to the input of the first photodetector, while the output of the frequency-locked loop is connected to the controlled input of the piezoelectric element of the deaf reflector, and the output of the phase-locked loop is connected to the controlled input of the phase modulator, characterized in that the second translucent dividing mirror, subtraction circuit, adder of the interference channel, adder of the correlation autocompensator of the signal, key circuit, signal simulator - a phase shifting phase by π / 2 circuit, a signal extraction circuit with a threshold circuit at its output, the output of the first translucent dividing mirror through the second translucent dividing mirror being connected to the inputs of the second and third photodetectors, and the output of the latter parallel connected to one of the inputs of the subtraction circuit directly and through the adder of the interference channel it is connected to the second input of the subtraction circuit, the output of which is connected to the input of the intra-period comb accumulation filter, in addition, the output of the third photodet the torus is connected to the main input of the adder of the correlation auto-compensator of the signal, to the auxiliary inputs of which the outputs of the first and second multipliers are connected, the outputs of which are also connected in parallel to the inputs of the signal extraction circuit and to the inputs of the key circuit, the outputs of which are connected to the inputs of the adder of the interference channel, while the controlled input the key circuit is connected with the output of the threshold circuit, in addition, the output of the response signal simulator with the input of the first multiplier and with one of the outputs of the first correlator is connected directly Actually, it is connected to the input of the second multiplier and the first input of the second correlator through a phase shifting circuit by π / 2, and the output of the adder of the correlation signal self-compensator is connected to the second inputs of the first and second correlators.