RU2010244C1 - Panoramic receiver - Google Patents

Abstract

FIELD: radio engineering. SUBSTANCE: panoramic receiver has first aerial 1, sweep generator 2, local oscillated 3, first mixer 4, first amplifier 5 of intermediate frequency, detector 6, scale-of-eight multiplier 7, first and second meters 8 and 9 of spectrum width, comparator 10, threshold unit 11, key 12, delay line 13, first multiplier 14, band-pass filters 15₁-15_n, amplitude detectors 16₁-16_n, video amplifiers 17₁-17_n, CRTs 18₁-18_n, second aerial 19, second mixer 20, second amplifier 21 of intermediate frequency, first and second 90 deg phase inverters 22 and 23, second and third multipliers 24 and 25, first and second low-pass filters 26 and 27, first and second squarers 28 and 29, adder 30, square root extracting unit 32, first single-polarity valve 32, first differentiating circuit 33, second single-polarity valve 34, (n+1)th amplitude detector 35, second differentiating circuit 36, count pulse generator 37, coincidence element 38, counter-divider 39 and register 40. EFFECT: expanded functional capabilities by way of accurate and single-valued direction finding of source of emission of phase-shifted signals. 3 dwg

Description

The invention relates to radio engineering and can be used to search and detect phase-shift (FM _n ) signals, as well as a visual assessment of their carrier frequency and direction finding of a radiation source.

 Known panoramic receiver, which contains a receiving antenna, a sweep generator, a local oscillator, a mixer, an intermediate frequency amplifier, an eight frequency multiplier, a second spectral width meter, a comparison unit, a threshold block, a key, a delay line, a multiplier and n processing channels, each of which consists of a series-connected bandpass filter, amplitude detectors, a video amplifier and a cathode ray tube.

It provides the search and detection of FM _n signals, as well as a visual assessment of their carrier frequency, but does not allow direction finding of the radiation source of FM _n signals.

 The aim of the invention is to expand the functionality by accurate and unambiguous direction finding of a radiation source of phase-shifted signals.

This goal is achieved by the fact that a second antenna, a second mixer, a second intermediate frequency amplifier, a first and second phase shifters of 90 ^° , a second and a third multiplier, a first and a second low-pass filter, a first and a second quadrator, an adder, a square extraction unit are introduced into the device the root, the first and second unipolar gates, the first and second differentiating circuits, the (n + 1) -th amplitude detector, counting pulse generator, coincidence element, counter-divider and registration unit, and to the output of the second antenna a second mixer is connected, the second input of which is connected to the output of the local oscillator, the second intermediate-frequency amplifier, the second multiplier, the second input of which is connected to the output of the first intermediate-frequency amplifier, the first low-pass filter, the first quadrator, adder, square root extractor, the first quadrator, adder, square root radiation unit, first unipolar valve, first differentiating circuit, second unipolar valve, counter-divider, the second input of which through the coincidence element connected to the outputs of the first unipolar valve and the counter pulse generator, and the third input is connected through the series-connected (n-1) -th amplitude detector and the second differentiating circuit to the output of the first intermediate frequency amplifier, and the recording unit, to the output of the second intermediate frequency amplifier connected in series to the first phase shifter ^90, third multiplier, a second input thereof via a second fazovraschatelna ⁹⁰ is connected to the output of the first intermediate frequency amplifier, a second low-pass filter is often and a second squarer output of which is coupled to a second input of the adder.

In FIG. 1 shows a structural diagram of the proposed receiver; in FIG. 2 - time diagrams explaining the operation of the receiver; in FIG. 3 - the principle of direction finding of a radiation source of FM _n signals by the phase method in one plane.

The panoramic receiver comprises a first antenna 1, a sweep generator 2, a local oscillator 3, a first mixer 4, a first intermediate frequency amplifier 5, a detector 6, an eight frequency multiplier 7, a first spectral width meter 8, a second spectral width meter 9, a comparison unit 10, threshold block 11, key 12, delay line 13, first multiplier 14, bandpass filters 15 ₁ -15 _n , amplitude detectors 16 ₁ -16 _n , video amplifiers 17 ₁ -17 _n , cathode ray tubes (CRT) 18 ₁ -18 _n , second antenna 19, second mixer 20, second intermediate frequency amplifier 21, first the first and second phase shifters 22 and 23 by 90 ^° , the second and third multipliers 24 and 25, the first and second low-pass filters 26 and 27, the first and second quadrants 28 and 29, the adder 30, the square root extractor 31, the first unipolar valve 32 , the first differentiator circuit 33, the second unipolar valve 34, the (n + 1) -th amplitude detector 35, the second differentiator circuit 36, the counter pulse generator 37, the coincidence element 38, the counter divider 39, and the registration unit 40.

Moreover, a local oscillator 3, a mixer 4, the second input of which is connected to the output of the antenna 1, an amplifier 5 of an intermediate frequency, a frequency multiplier 7, a measuring device 9 of the spectrum, a comparison unit 10, the second input of which through a measuring device 8 is connected in series to the output of the antenna 2, are sequentially connected the spectrum is connected to the output of the intermediate frequency amplifier 5, the threshold unit 11, key 12, the second input of which is connected to the output of the intermediate frequency amplifier 5, a delay line 13, a multiplier 14, the second input of which is connected to the output of the key 12, and n processing channels, each of which consists of a series-connected narrow-band filter 15 _i , an amplitude detector 16 _i , a video amplifier 17 _i and a vertical CRT electrode 18 _i (i = 1,2, ..., n), the horizontal electrode of which is connected to the second output of the generator 2 sweep. To the output of the antenna 19, a mixer 20 is connected in series, the second input of which is connected to the output of the local oscillator 3, an intermediate frequency amplifier 21, a multiplier 24, the second input of which is connected to the output of the intermediate frequency amplifier 5, a low-pass filter 26, a quadrator 28, an adder 30, block 31 square root extraction, a unipolar valve 32, a differentiating circuit 33, a unipolar valve 34, a counter divider 39, the second input of which is connected through the coincidence element 38 to the outputs of the unipolar valve 32 and the counter pulse generator 37, third input through series-connected amplitude detector 35 and the differentiating circuit 36 connected to the output of intermediate frequency amplifier 5, and the registration unit 40. To the output of amplifier 21, intermediate frequency series connected phase shifter 22 to ^90, a multiplier 25, a second input of which through the phase shifter 23 to ⁹⁰ connected to the output of the amplifier 5, an intermediate frequency filter 27, low pass, and a squarer 29, which output is coupled to a second input of the adder 30 .

 Panoramic receiver operates as follows.

Viewing predetermined frequency band D _f by means of sweep generator 2 which are periodically with period T _n rearranges sawtooth oscillator frequency 3. Simultaneously sweep generator 2 generates a horizontal scan CRT January ₁₈ -18 _n, which is used as a frequency axis, wherein the length corresponds to the frequency span D _f . The key 12 in the initial state is always closed.

=

- время запаздывания сигнала, приходящего на одну антенну, по отношению к сигналу, приходящему на другую антенну (см. фиг. 3);
d - расстояние между антеннами (измерительная база);
β - угол прихода радиоволны;
с - скоpость распространения света, с выходов антенн 1 и 19 поступают соответственно на первые входы смесителей 4 и 20, на вторые входы которых подается напряжение гетеродина 3 линейноизменяющейся частоты
u_г(t)= U_гcos(ω_гt+πγ₁t²+φ_г), ,
0 ≅ t ≅ T_п, где U_г, ω_г, φ_г, Т_п - амплитуда, начальная частота, начальная фаза и период повторения напряжения гетеродина соответственно,
γ₁=

- скорость изменения частоты гетеродина (скорость изменения первой гармоники гетеродина).Received FM _n signals
u ₁ (t) = U _with cos [ω _with t + φ _к (t) + φ ₁ ] = U _with M (t) cos (ω _with t + φ ₁ ),
u ₂ (t) = U _with cos [ω _with t + φ _к (t) + φ ₂ ] = U _with M (t + τ) cos [ω _with t + τ) + φ ₂ ],
0 ≅ t ≅ T _c , where U _c , ω _c , T _c , φ ₁ , φ ₂ - amplitude, carrier frequency, duration and initial phases of signals;
φ _k (t) is the manipulated component of the phase, which displays the law of phase manipulation in accordance with the modulating function M (t), and φ _k (t) = const for kτ _u <t <(k + 1) τ _u and can change abruptly by Δφ at t = k τ _u , i.e., at the boundaries between elementary premises (k = 0,1,2,..., N-1);
τ _u , N is the duration and number of chips that make up signals with a duration of T _s (T _s = τ _u N);
M (t) is the modulating function, in accordance with which the phase of the signals is manipulated;
τ =

=

- the delay time of the signal arriving at one antenna with respect to the signal arriving at another antenna (see Fig. 3);
d is the distance between the antennas (measuring base);
β is the angle of arrival of the radio wave;
c is the speed of light propagation, from the outputs of antennas 1 and 19 are supplied respectively to the first inputs of the mixers 4 and 20, the second inputs of which are fed the voltage of the local oscillator 3 of a ramp frequency
u _g (t) = U _g cos (ω _g t + πγ ₁ t ² + φ _g ),,
0 ≅ t ≅ T _p , where U _g , ω _g , φ _g , T _p - amplitude, initial frequency, initial phase and the repetition period of the local oscillator voltage, respectively,
γ ₁ =

- rate of change of the local oscillator frequency (rate of change of the first harmonic of the local oscillator).

k₁U_cU_г;
k₁ - коэффициент передачи смесителей;
ω_пр= ω_c-ω_г - промежуточная частота;
φ_пр1= φ₁ - φ_г, φ_пр2= φ₂-φ_г, , которые представляют собой сигналы с комбинированной линейной частотой модуляцией и фазовой манипуляцией (ЛЧМ-ФМ_н).At the output of the mixer 4 and 20, voltages of combination frequencies are generated. Amplifiers 5 and 21 are allocated voltage intermediate (differential) frequency
u _pr1 (t) = U _pr cos [ω _pr t + φ _к (t) -Πγ ₁ t ² + φ _pr1 ] =
= U _pr M (t) cos (ω _pr t-Πγ ₁ t ² + φ _pr 1);
u _pr2 (t) = U _pr cos [ω _pr t + φ _к (t) -Πγ ₁ t ² + φ _pr2 ] =
= U _pr M (t + τ) cos [ω _pr (t + τ) -Πγ ₁ t ² + φ _pr2 ], 0≅ t≅ T _s ,
0 ≅ t ≅ T _c where U _pr =

k ₁ U _c U _g ;
k ₁ - gear ratio of the mixers;
ω _CR = ω _c -ω _g is the intermediate frequency;
φ _CR1 = φ ₁ - φ _g , φ _CR2 = φ ₂ -φ _g , which are signals with combined linear frequency modulation and phase shift keying (LFM-FM _n ).

The voltage u _pr1 (t) from the output of the intermediate frequency amplifier 5 is fed to the input of the detector 6, consisting of a frequency multiplier 7, eight meters, spectral width meters 8 and 9, a comparison unit 10, a threshold block 11, and a key 12. At the output of the frequency multiplier 7 eight voltage is formed
u ₃ (t) = U _pr cos (8ω _pr t-8Πγ ₁ t ² + 8φ _pr1 ), 0≅ t≅ T _s .

0;

; Π;

) и 8 φ_k(t)= { 0; 2 π ; 4π ; 6π ; 10 π ; 12 π ; 14 π } при приеме сигнала с трехкратной фазовой манипуляцией (ФМ_н-8, φ_к(t) =

0;

;

;

Π; Π;

Π;

Π;

). Следовательно в указанном напряжении u_з(t) при ФМ_н-2, ФМ_н-4 и ФМ_н-8 манипуляция фазы уже отсутствует.Since the phase value 8 φ _k (t) takes one of the values 8 φ _k (t) = {0; 8 π} when receiving a signal with a single phase shift keying (FMN-2, φ _k (t) = {0; π}, then the phase value takes one of the values 8 φ _k (t) = {0; 4π; 8π; 12π} when receiving a signal with double phase shift keying (FMN-4, φ _к (t) =

0;

; Π;

) and 8 φ _k (t) = {0; 2 π; 4π; 6π; 10 π; 12 π; 14 π} when receiving a signal with three-fold phase shift keying (FM _n -8, φ _к (t) =

0;

;

;

Π; Π;

Π;

Π;

) Therefore, in the indicated voltage u _s (t) with FM _n -2, FM _n -4 and FM _n -8, phase manipulation is already absent.

), тогда как ширина спектра принятого ФМ_н сигнала определяется длительностью τ_u его элементарных посылок (Δf_с =

) , т. е. ширина спектра восьмой гармоники сигнала в N раз меньше ширины спектра входного сигнала

= N.The width of the spectrum Δ f _{8 of the} eighth harmonic is determined by the duration T of _the signal (Δf ₈ =

), while the spectrum width of the received FM _n signal is determined by the duration τ _{u of} its elementary premises (Δf _c =

), i.e., the spectrum width of the eighth harmonic of the signal is N times smaller than the spectrum width of the input signal

= N.

Therefore, when the frequency of the FM _n signal is multiplied by eight, its spectrum is “folded” N times. This circumstance makes it possible to detect the FM _n signal in a narrow frequency band determined by the bandwidth of the narrow-band filter 15 even when its power at the receiver input is less than the average noise power.

The width of the spectrum Δf _{from the} input FM _n signal is measured using meter 8, and the spectrum width Δf _{8 of the} eighth harmonic of the signal is measured using meter 9. Voltages U and U ₈ proportional to Δf _c andΔ f _8, respectively, come from the output of meters 8 and 9 of the spectrum width on two inputs of block 10 comparison. Since U >> U ₈ , a positive voltage is generated at the output of the comparison unit 10, which exceeds the threshold level U _then in the threshold block 11. The threshold level U _then is selected so that it does not exceed random interference. When the threshold level U _pores is exceeded, a constant voltage is generated in the threshold block 11, which is supplied to the control input of the key 12, opening it.

K₂U $\genfrac{}{}{0ex}{}{\text{2}}{\text{п}}$ _р;
k₂ - коэффициент передачи перемножителя 14;
ω_б1= 2πγ₁τ_з- частота биений;
φ_k1(t)= φ_k(t-τ_з)-φ_k(t);
φ_б1= ω_прτ_з+πγ₁τ_з ² - начальная фаза биений.In this case, the voltage u _pr1 (t) from the output of the intermediate frequency amplifier 5 through the public switch 12 is simultaneously supplied to the first input of the multiplier 14 and to the input of the delay line 13, at the output of which a voltage is generated
u _pr3 (t) = U _pr1 (t-τ ₃ ) = U _pr cos [ω _pr (t-τ ₃ ) + φ _к (t-τ ₃ ) -
-Πγ ₁ (t-τ ₃ ) ² + φ _pr1 ], 0≅ t≅ T _s , where τ _s is the delay time of the delay line 13. This voltage is supplied to the second input of the multiplier 14, the output of which produces a voltage
u _b1 (t) = U _b cos [ω _b1 t + φ _k1 (t) + φ _b1 ],
0 ≅ t ≅ T _c , where U _b =

K ₂ U $\genfrac{}{}{0ex}{}{\text{2}}{\text{P}}$ _p ;
k ₂ - transfer coefficient of the multiplier 14;
ω _b1 = 2πγ ₁ τ _s - beat frequency;
φ _k1 (t) = φ _k (t-τ _h ) -φ _k (t);
φ _b1 = ω _pr τ _z + πγ ₁ τ _z ² - the initial phase of the beats.

The frequency ω _b1 of the beat voltage u _b1 (t) is equal to ω _b1 = 2πγ ₁ τ _s = const. Consequently, with a fixed delay time τ _s , a mono-frequency beat signal is generated at the output of multiplier 14, the frequency ω _{b1 of} which depends on the rate of change of the frequency γ _i (i = 1, 2,..., N) of the local oscillator 3. The rate of change of the frequency of the converted signal, coming to the input of the autocorrelator, consisting of a delay line 13 and a multiplier 14, depends on the harmonic number of the local oscillator frequency 3, interacting with the carrier frequency of the received FM _n signal.

The tuning frequency ω _{n1 of the} narrow-band filter 15 ₁ is chosen equal to
ω _n1 = ω _b1 = 2πγ ₁ τ _s , the tuning frequency ω _{n2 of the} narrow-band filter 15 ₂ is chosen equal to
_2n ω = ω _b2 = 2πγ τ _{2 s,} and the tuning frequency ω _Hn narrowband filter 15 is chosen equal to _n
ω _nn = ω _bn = 2πγ _n τ _s , where γ _n = nγ ₁ is the rate of change of the nth harmonic of the local oscillator frequency.

The voltage u _bi (t) from the output of the narrow-band filter 15 _{i is} supplied to the input of the amplitude detector 16 _i , where it is detected and, after amplification in the video amplifier 17 _{i, is} applied to the vertical electron of the CRT 18 _i , on the screen of which a pulse is generated (frequency mark). The position of the frequency mark on the horizontal scan of the CRT 18 _i uniquely determines the carrier frequency ω _{c of the} received FM _n signal (i = 1, 2,..., N).

Consequently, the harmonic number of the local oscillator frequency 3, with which the carrier frequency of the received FM _n signal interacts, is determined by the number of the band-pass filter of that channel on the CRT screen of which a frequency mark is observed.

cos β, где λ - длина волны;
d - база пеленгатора;
β - угол прихода сигнала относительно нормали к базе.For direction finding of radiation sources of signals, the phase method is widely used, in which the phase difference Δφ of signals received by two spaced antennas is determined by the expression
Δφ = 2Π

cos β, where λ is the wavelength;
d is the base of the direction finder;
β is the angle of arrival of the signal relative to the normal to the base.

. Но с ростом

уменьшается значение угловой координаты, при котором разность фаз Δφ не превосходит значение 2π (условие однозначного отсчета угла), т. е. наступает неоднозначность отсчета.However, the phase method of direction finding is characterized by a contradiction between the requirements for the accuracy of measurements and the uniqueness of the angle reading (the direction of wave incidence). According to the above formula, the phase system is the more sensitive to a change in angle, the larger the relative size of the base

. But with growth

the value of the angular coordinate decreases, at which the phase difference Δφ does not exceed 2π (the condition for a unique reference of the angle), i.e., the ambiguity of the reference occurs.

There are two ways to eliminate the ambiguity of the phase method of direction finding of a radiation source of an FM _n signal: using highly directional antennas and using several measurement bases (multi-scale).

 Direction finding systems with highly directional antennas have a long range and high resolution in direction. However, they require a search for the source of radiation of the signals before measurements and their automatic tracking in the direction of the antenna beam during the measurement process, and also deprive the phase method of direction finding of one of its advantages - the possibility of using non-directional (isotropic) antenna systems.

 Multi-scalability is usually achieved using several measurement bases. At the same time, a smaller base forms a rough but unambiguous reference frame for the angle, and a large base forms an accurate but ambiguous reference frame. Direction finding systems using this method have a limited range and complex technical implementation.

In the proposed receiver for accurate and unambiguous direction finding of a radiation source of FM _n signals, a modified phase method is used, based on quadrature correlation processing of received signals.

(t)= U_бM(t)M(t+τ)cos(ω_прτ+
+Δφ)+U_бM(t)M(t+τ)cos(2ω_прt+ω_прτ-2Πγ₁t²+

+

), 0≅ t≅ T_с , где U_б=

K₂U $\genfrac{}{}{0ex}{}{\text{2}}{\text{п}}$ _р.For this voltage, u _pr1 (t) and u _pr2 (t) from the outputs of the amplifiers 5 and 21 of the intermediate frequency are fed to two inputs of the multiplier 24, the output of which produces the resulting oscillation
u

(t) = U _b M (t) M (t + τ) cos (ω _pr τ +
+ Δφ) + U _b M (t) M (t + τ) cos (2ω _pr t + ω _pr τ-2Πγ ₁ t ² +

+

), 0≅ t≅ T _s , where U _b =

K ₂ U $\genfrac{}{}{0ex}{}{\text{2}}{\text{P}}$ _r .

cos(ω_прτ+Δφ)

= 1;
ω_прτ = πk; k = 0, 1, 2, . . . ,
Δφ= 0.From the resulting resulting oscillation, a low-pass filter 26 with a cutoff frequency ω _pr distinguishes the voltage of the difference frequency u _p1 (t) = U _b M (t) M (t + τ) cos (ω _pr τ + Δφ), 0 ≅ t ≅ T _c proportional to the correlation function of the signals u _CR1 (t) and u _CR2 (t). To obtain the maximum value of the correlation function, it is necessary to fulfill the following condition:

cos (ω _pr τ + Δφ)

= 1;
ω _pr τ = πk; k = 0, 1, 2,. . . ,
Δφ = 0.

(t) = U_прM(t)cos(ω_прt-Πγ₁t²+

+90^°) = U_прM(t)sin(ω_прt-Πγ₁t²+

),
u

(t)= U_прM(t+τ)cos[ω_пр(t+τ)-Πγ₁t²+

+90^°=
= U_прM(t+τ)sin[ω_пр(t+τ)-Πγ₁t²+

] , 0≅ t≅ T_с.However, with instability of the carrier frequency of the received FM _n signals and with a change in τ, this condition is very difficult to fulfill. To fulfill this condition, it is proposed to use quadrature processing of the received FM _n signals. To this end, the voltages u _pr1 (t) and u _pr2 (t) from the outputs of the amplifiers 5 and 21 of the intermediate frequency are simultaneously supplied to the inputs of the phase shifters 23 and 22 by 90 ^° , the outputs of which generate voltages
u

(t) = U _pr M (t) cos (ω _pr t-Πγ ₁ t ² +

+90 ^° ) = U _pr M (t) sin (ω _pr t-Πγ ₁ t ² +

),
u

(t) = U _pr M (t + τ) cos [ω _pr (t + τ) -Πγ ₁ t ² +

+90 ^° =
= U _pr M (t + τ) sin [ω _pr (t + τ) -Πγ ₁ t ² +

], 0≅ t≅ T _s .

(t)= U_бM(t)M(t+τ)sin(ω_прt+Δφ)+
+U_бM(t)M(t+τ)sin[2ω_прt+ω_прτ-2Πγ₁t²+

+

] , 0≅ t≅ T_с.These voltages are applied to the two inputs of the multiplier 25, at the output of which the resulting oscillation is formed
u

(t) = U _b M (t) M (t + τ) sin (ω _pr t + Δφ) +
+ U _b M (t) M (t + τ) sin [2ω _pr t + ω _pr τ-2Πγ ₁ t ² +

+

], 0≅ t≅ T _s .

(t)= U_бM(t)M(t+τ)sin(ω_прτ+Δφ), 0≅ t≅ T_с.From the resulting resulting oscillation by the low-pass filter 27, the voltage of the differential frequency is allocated
u

(t) = U _b M (t) M (t + τ) sin (ω _pr τ + Δφ), 0≅ t≅ T _s .

(t)+U $\genfrac{}{}{0ex}{}{\text{2}}{\text{р}}$ (t)= [U_бM(t)M(t+τ)] ²[cos²(ω_прτ+Δφ)+
+sin²(ω_прτ+Δφ)] = [U_бM(t)M(t+τ)] ².Voltages u _p1 (t) and u _p2 (t) through the squares 28 and 29 are fed to the two inputs of the adder 30, the output of which is formed by the total voltage
u _Σ (t) = U

(t) + U $\genfrac{}{}{0ex}{}{\text{2}}{\text{R}}$ (t) = [U _b M (t) M (t + τ)] ² [cos ² (ω _pr τ + Δφ) +
+ sin ² (ω _pr τ + Δφ)] = [U _b M (t) M (t + τ)] ² .

 This voltage is supplied to the input of the square horse extraction unit 31, at the output of which a low-frequency voltage is generated (see Fig. 2, f).

, где τ_i - длительность i-го отрицательного импульса на выходе однополярного вентиля 32;
n - объем выборки (количество измерений).u _n (t) = U _b M (t) M (t + τ), which is the product of the modulating function which is the product of the modulating function M (t) (see Fig. 2, a) and its copy shifted by τ M (t + τ) (see Fig. 2, d). The voltage u _n (t) is supplied to the input of a unipolar valve 32, at the output of which negative impulses are generated (see Fig. 2, g) of duration τ. These pulses are fed to the input of the differentiating circuit 33, at the output of which short short-polarity pulses are formed (see Fig. 2, h). The unipolar valve 34 passes to its output only negative short pulses (see Fig. 2, and), which are fed to the first input of the counter-divider 39. Counted pulses (see Fig. 2, k) from the output of the generator 37 counted pulses through the element coincidence 38, to the second input of which negative pulses are fed (see Fig. 2g) from the output of the unipolar valve 38, are fed to the second input of the counter-divider 39, in which the counting pulses are sequentially added and the resulting sum is divided by the number of measurements
τ _avg =

where τ _i is the duration of the i-th negative pulse at the output of the unipolar valve 32;
n is the sample size (number of measurements).

The voltage u _pr1 (t) (see Fig. 2, b) from the output of the intermediate frequency amplifier 5 is simultaneously supplied to the input of the amplitude detector 35, which selects its envelope (see Fig. 2, c). The latter enters the input of the differentiating circuit 36, at the input of which two differently short short pulses are formed (see Fig. 2, d). Moreover, with a short positive pulse, the counter-divider 39 is restored to the initial (zero) state, and with a negative short pulse, the number of counting pulses proportional to τ _cp is recalculated to the registration unit 40. The value of τ _cp fixed in the digital code uniquely determines the angle of arrival of the radio wave β.

Thus, the proposed receiver in comparison with the prototype provides accurate and unambiguous direction finding of the radiation source FM _n signals. Moreover, the high accuracy of direction finding is achieved by increasing the measuring base d, and the resulting ambiguity in reading the angular coordinate is eliminated by quadrature correlation processing of the received FM _n signals, at which the average delay time τ _cp in the digital code is measured. The measured value of τ _cp uniquely determines the angle of arrival β of the radio wave. Thus, the functionality of the panoramic receiver is expanded.

 In addition, the presentation of direction finding results in digital code ensures their long-term storage, long-distance transmission via communication channels and interfacing with computer technology. (56) Copyright certificate of the USSR 1661661, cl. G 01 R 23/00, 1990.

Claims (1)

A PANORAMIC RECEIVER containing a first-round first-order antenna, a first mixer, a second input of which through a LO is connected to the first output of a frequency generator, a first intermediate frequency amplifier, an eight-speed frequency multiplier, the spectrum is connected to the output of the first intermediate-frequency amplifier, a threshold block, a key, the second input of which is connected to the output of the first intermediate-frequency amplifier, the delay line will multiply Or, the second input of which is connected to the output of the key and the processing channels, each of which consists of a series-pass bandpass filter, an amplitude detector, a video amplifier and a vertical electrode of an electron beam tube, a horizontal electrode of which is connected to the second, second in order to expand functionality by accurately and unambiguously determining the radiation source of phase-shifted signals, a second antenna, a second mixer, and a second amplifier are introduced into it weft frequency pe.pvyy and vto.poy fazovpaschateli 90 ^o, vto.poy and by the third pepemnozhiteli, pe.pvyy and vto.poy The filters mnozhnih frequencies pe.pvyy and vto.poy kvadpatopy, summatop, extracting unit kvadpatnogo kopnya, pe.pvyy and vto.poy odnopolyapnye valves, southern and northern and vto.poy diffepentsipuyuschie chain, (n + 1) amplitude detector, counting pulse generator, coincidence element, divider counter and registration unit, in which the second mixer is connected in series to the second antenna, the second input of which is connected to the local oscillator output, and the second intermediate frequency amplifier, second a second multiplier, the second input of which is connected to the output of the first intermediate-frequency amplifier, the first low-pass filter, the first quadrator, the adder, the square root extraction unit, the first unipolar valve, the first differentiating circuit, and the other coincidence is connected to the outputs of the first unipolar valve and the generator of the counting pulses, and the third input through the series-connected (n + 1) -th amplitude detector and the second differentiating circuit is connected to the output of the alarm about the intermediate frequency amplifier, and the registration unit, to the output of the second intermediate frequency amplifier, the first 90 ^o phase shifter, the third third multiplexer, the second input of which the second second and second frequency phase shifter, 90 ^{o are} connected to the first and second frequency second and second frequency amplifier , the output of which is connected to the second input of the adder.

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