SU1048582A2 - Device for synchronous detection of phase-shift-keyed signals - Google Patents

Description

The invention relates to radio engineering, can be used in apparatus designed to receive and analyze broadband aero manipulated (FMN) signals.

According to the main auth. No. 978288. A device for synchronous detection of phase-modulated signals is known, comprising a first phase detector, a decoder, a reference oscillator, the output of which is connected to one input of a second phase detector, a serially connected frequency multiplier, a narrowband filter, a third phase detector, a control unit, a local oscillator, a mixer, and a bandpass filter as well as optional. the frequency multiplier, the first and second reference voltage formers, the adder and the fourth phase detector, the output of the bandpass filter connected to the combined inputs of the frequency multiplier, the first input of the first phase detector and another input of the second phase detector, the output of which is through the sequentially connected adder and the fourth the phase detector is connected to the input of the decoder, the output of the additional frequency multiplier is connected to the combined second input of the first phase detector and the first inputs of the generator reference frequency, the second inputs of which are combined and connected to the output of the reference oscillator connected to the input of an additional frequency multiplier, the output of the first frequency reference former is connected to another input of the third phase detector, the output of the second reference voltage former is connected to another input of the fourth phase detector, the output of the first phase detector is connected to another input of the adder, and the other input of the mixer is the input of the device Ul.

However, the known device provides noise-resistant detection of only FMN signals.

The purpose of the invention is to detect signals with amplitude and frequency modulation.

This goal is achieved by introducing a series-connected amplitude limiter, multiplier, low-pass filter, synchronous detector, first modulating function analyzer and registration trees, to the second input of which the second analyzer entered is inserted, and the third input is connected to the device for synchronous detection of phase-shift keyed signals. the registration unit is connected to the output of the decoder; you: the course of the third phase detector is connected to the input of the second angling detector.

modulating function, the output of the first phase detector is connected to the input of the amplitude limiter, the second input of the multiplier is connected to the output of the second phase detector, and the output of the reference generator is connected to another input of the synchronous detector.

The drawing shows a structural electrical circuit of the proposed device.

The device contains a mix 1, a local oscillator 2, a band-pass filter 3f, a reference generator 4, an additional frequency multiplier 5, drivers 6 and 7: reference voltage, phase detectors 8 and 9, adder 10, phase detector 11, decoder 12, frequency multiplier 13, narrowband filter 14, phase detector 15, flea control 16, amplitude limiter 17, multiplier 18, low pass filter 19, synchronous detector 20, analyzers 21 and 22 of the modulating function, recording unit 23.

The device works as follows.

Take the signal with phase shift keying,

OSH-UcOOs Luct -),

where () with amplitude and carrier frequency of the signal}

4 "(t) manipulated phase component, representing the law of phase manipulation, in accordance with the modulating code, prtl4eM (Ktt) CO№tnpH. (K + And may change abruptly with -fe KTg, i.e. on the boundaries between elementary premises (to O, 1, 2,. ...- Ij

Cg, is the duration and the number of elementary parcels from which the signal of duration 1Г 5) is composed: Ntg;

enters the first input of the mixer 1, n & the second input of which is applied the voltage of the local oscillator 2

Ura) - UrC05 "; rt-.

As a result of frequency conversion, a FMN signal is generated at the first. intermediate frequency

Unp W U cosCUJnpt + vf to ShZ, where

K. - transmission coefficient of the frequency converter 3;

(i) r, t Р промежуточ Я intermediate frequency.

This signal is emitted by a bandpass filter 3 and is divided into two channels. The reference signal is supplied from the reference generator 4 to the reference input of the phase detector 8 of the first channel. (, COV1 "G. This signal is multiplied in frequency by two in the multiplier 5 Ur, U)" Ubcos U, (. T) UoCOSU) r .: and the reference input of the phase detector of the second channel comes in, 9 the frequency "/ n, and, and are chosen to be symmetric: with respect to the first intermediate part of the set η; pr, i.e.% -%. The phase detector provides a serially connected multiplier and a low-pass filter, so after multiplying, the following voltages are formed in each channel: U, (ife) U4CosUurnp- yrV) tt4Ka) I + U.lt05Uu; np + "r :,) 4icUp ( tbUaC oet ()) l fUaCosUi “ra + iynp) t + CHESH where Ujj. . Kg is the transmission coefficient of the phase detectors 8 and 9. Of these voltages, the difference frequency frequencies are separated from the low-pass filters, therefore the following voltage corresponding to the output of the phase detectors 8 and 9 are: UiU) Uicos UcUnp-t%, Wl O Ct liuCO -iUW-h prN- to W. where UW is the voltage difference voltage in the first channel. OjjCi) - voltage. difference frequency in the second channel. . The voltages Q (-fc) and C-t) are added up in the adder 10, .. -. (.i) -Oaa) + Oitt) -U2cos Cujnpt: iCari ttnr) fc ticWl Co5 and go to the information input. phase detector 11, on the reference; the input of which is supplied from the output: form1 of the sensor 7, the reference voltage Oo () UoCOs - t, (whose frequency is equal to the half-difference of the frequencies of the reference signals (Jp (t) and Or.t Ct) As a result of synchronous 01 {Detection at the output of phase Detector 11 the following voltage is UjTlrD-UMCOsBibinp i5- -tl Ktt) 3-OHC054iCt), where OH is -J K U2., Ue, 1Сз is the transfer coefficient of the phase detector 11, -O, because frequencies 2 Fr and / rdg are symmetrical with respect to frequency (f pr Low frequency voltage UK (i) is analogous to the modulating code. According to which the phase (t) of the received of the signal (/ c W, enters the decoder 12, where the basic parameters of the modulating code are determined (the duration of the elementary premises T; the number N and the phase coding law). These parameters are recorded in block 23 .. To ensure the symmetry of the frequencies Wr4 and (f Ga. Support signals Op) (t) and rc.Cfc) relative to the first intermediate frequency of the QPSF OPD signal (4 uses a phase self-tuning system consisting of a series-connected frequency multiplier 13, phase detector 15, the second% of which is connected to the heterodyne 2 Transformed FMN signal UnpCtbUn COS CWnpi) with Otn from the output of the band-pass filter 3 rep-. blunt on the input of the multiplier 13 frequency (two), the output of which produces the following harmonic oscillation UM (-tbU-, with S С4 t + 2 VK (t) U with s 2ounp, where 2 Chz (t) 0,2%, which in phase detector 15 is compared in phase with the controversial voltage Ioa Ctb C "gI yHH OOC052 (t, received from the output of the former 6. If the indicated voltages differ from each other in phase, then the output of the phase detector 15 is released) The amplitude and polarity of this voltage will depend on the degree and direction and deviation of the intermediate frequency from the sums Wf + Gu frequencies of reference signals. The control voltage through the control unit 16 affects the local oscillator 2 by changing its frequency so that the intermediate frequency k) is symmetrical relative to the frequencies (4) 1 Gp of the reference signals. at the input of the frequency-modulated (FM) signal, the parameters of the phase-locked loop system are chosen so that the local oscillator 2 tracks the changes. frequency of received FM signal in accordance with the law of frequency modulation. In this case, the low-frequency voltage at the output of the phase detector 15 displays the law of the frequency modulation of the received FM signal. This voltage is analyzed by the analyzer 22 of the modulating function and recorded by block 23. If the device receives an amplitude-modulated CAM), the signal I OS ttb Jw W COS CWt-t4), where I is the frequency and the initial factor for the signal F OpsH-modulating function, then it is also frequency transformed; in mixer 1; bandpass filter 3 is allocated at the first intermediate frequency (Unptt) U) COS (Shpr-t 1-Ch) udede) - | -K, 0 WUp, and then separated on two channels in each of which the second signal is converted by frequency At the output of the phase detectors 8 and 9, the following voltages 14 (Sh) are given: SoSiSipr-Shg,; Uiti) Oatt) cosCO% -uwnp) where U5. (I)) Uo The indicated voltages after the preliminary limitation on the amplitude of one of them in the amplitude limitation of Tele 17 are multiplied in multiply 1 Le 18, the output of which results in the resultant oscillation and Sig1wx5 {sn4 -h g H) coe; t i "np -tHr,) i.), de UyC-t} - f-K U transfer coefficient nejje, multiplication 18.. From the resultant resultant krlebani filter set of the 19 lower frequencies, the voltage of the varied ch1) rsH-CU: Creates the voltage from the STRETCHED S1MSHITITO with the VYHRDa reference generator Up, U) -UoC05tWn, i. A synchronous detector 20 provides synchronous detection of a receiving AM signal, and the information about the Pb amplitude modulation is analyzed in the English 21 modulating function T, recorded and blr-. . -. : In this way, the proposed device provides the Lnya- pre-crack command. New detection of non-TRLKF ph: aomanipulated signals, np, and signals with scatterplex and partial modulation. Thus, the functional capabilities of the device compared with the prototype significantly expanded w. When eprm, the instability of the carrier part is eliminated, the food supply is due to various destabilizing factors, for example, the Drppler effect, changes in the radius of the radio, equipment instability, etc.

Claims (1)

DEVICE FOR SYNCHRONOUS DETECTION OF PHASOMANIPULATED SIGNALS by ed. St. * 978288, excluding the fact that, in order to detect signals with amplitude and frequency modulation, series-connected are introduced: 'amplitude limiter, multiplier, low-pass filter, synchronous detector, first analyzer of the modulating function and a registration unit, to the second input of which the entered second analyzer of the modulating function is connected, the third input of the registration unit being connected to the output of the decoder, the output of the third phase detector connected to the output of the second analyzer of the modulating function, output d a first phase detector coupled to an input of the amplitude limiter pe.remnozhitelya second input connected to the output of the second phase detector, and an output coupled to the reference oscillator _ On the other gim § · input of the synchronous detector. S U mtJ 048582