RU1809308C - Indication device - Google Patents

Abstract

The invention relates to the field of instrumentation and can be used to index rapidly changing processes, in order to increase the reliability of a visual assessment of the main parameters of the received signal, two amplitude detectors, a video amplifier, a comparison unit, a unipolar valve, a third, fourth, fifth and the sixth key, and the first amplitude detector, video amplifier, comparison unit, the second input of which is through the second amplitude amplifier, are connected in series to the second output of the broadband amplifier The first detector is connected to the output of the intermediate-frequency amplifier, and the third key, connected between the output of the intermediate-frequency amplifier and the first input of the first key, is connected to the output of the first differentiating circuit by a unipolar valve and a fourth key connected between the output of the sweep generator and the horizontally deflecting plates of the first a cathode ray tube, between the detector output and vertically deflecting plates of the second cathode ray tube, a fifth key is included, a second input of which о is connected to the output of the unipolar valve, between the output of the second key and the input of the second frequency detector, the sixth key is connected, the second input of which is connected to the output of the unipolar valve. 4 ill. . ate with

Description

The invention relates to indicator and recording devices and can be used to indicate rapidly changing processes, in particular, to visually analyze and record the parameters of complex signals with combined linear frequency modulation and multiple phase shift keying (LFM-MPSK).

The aim of the invention is to increase the reliability of the visual assessment of the main parameters of the received signal by suppressing additional reception channels.

Figure 1 presents a structural diagram of the proposed device; figure 2 structural diagram of the detector of complex signals; in Fig.Z - possible waveforms; Fig. 4 is a frequency diagram illustrating a process for generating additional receive channels; Fig. 4 is a timing chart illustrating the operation of the device.

The indicator device comprises a sweep generator 1, a first CRT 2, a receiving antenna 3, a broadband amplifier 4, a first frequency detector 5, a first differentiating circuit 6, a second differentiating circuit 7, a mixer 8, an intermediate frequency amplifier 9, a first key 10, a first frequency multiplier 11 at eight, the first band-pass filter 12, the first

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frequency divider 13 by eight, second, bandpass filter 14, multiplier 15, third bandpass filter 16, second frequency multiplier 17 by eight, fourth bandpass filter 18, second frequency divider 19 by eight, fifth bandpass filter 20. phase detector 21, filter 22 low frequencies, control signal driver 23, controlled delay element 24, detector 25, delay element 2.6, second key 27, search unit 28, local oscillator 29, second private detector 30, phase shifter 31 90 °, reference voltage generator 32 second and third CRT 33 and 34, first and second ohm amplitude detectors 35 and 36, video amplifier 37, comparison unit 38, third key 39, one-way valve 40, fourth, fifth and sixth keys 41, 42 and 43. Moreover, a broadband amplifier 4, a mixer are connected in series to the output of the antenna 3 8, the second input of which through the local oscillator 29 is connected to the output of the search unit 28, an intermediate frequency amplifier 9, an amplitude detector 36, a comparison unit 38, the second input of which is connected through a series-connected amplitude detector 35 and a video amplifier 37 to the second output of the broadband amplifier 4 , a key 39, the second input of which is connected to the output of the intermediate frequency amplifier 9, a key 10, the second input of which is connected to the output of the detector 25, a frequency multiplier 11 by eight, a band-pass filter 12, a frequency divider 13 by eight, a band-pass filter 14, a frequency detector 5, a differentiating circuit 6, a differentiating circuit 7, a sweep generator 1, a key 41, the second input of which through a one-way valve 40 is connected to the output of the differentiating circuit 6, and a horizontally-deflecting plate CRT 2, vertically-deflecting plates of which are connected to the output ohm of the differentiating circuit 6. To the amplifiers 9 of the intermediate frequency, a multiplier 15 is connected in series, the second input of which is connected via the controlled delay element 24 to the output of the bandpass filter 14, the bandpass filter 16, the frequency multiplier 17 by eight, the bandpass filter 18, the frequency divider 19 by eight, a bandpass filter 20, a phase detector 21, the second input of which is connected to the output of the reference voltage generator 32, a low-pass filter 22 and a control signal generator 23, the output of which is connected to the second input of the element 24 controlled delays. A detector 25 is connected in series to the output of the intermediate-frequency amplifier 9, the second input of which is connected via its delay element 26 to the output, a key 42, the second input of which is connected to the output of the unipolar valve 40, and the vertical-deflecting plates of the CRT 33, which are horizontally deflecting the plates of which are connected to the second output of the search unit 28. The output of the reference voltage generator 32 is connected in series

a 90 ° phase shifter 31 and horizontal deflecting plates of a CRT 34, vertical deflecting plates of which are connected to the output of the reference voltage generator 32. To detector output

25, the key 27 is connected in series, the second input of which is connected to the output of the bandpass filter 16, the key 43, the second input of which is connected to the output of the unipolar valve 40, the frequency detector 30

and a modulating electrode CRT 34.

The device operates as follows.

The specified frequency range Df is viewed with the help of the search unit 28, which periodically with the period Тп according to the sawtooth law tunes the frequency of the local oscillator 29. At the same time, the search unit 28 forms a horizontal scan of the CRT 33, which is used as the axis

frequencies, and its length corresponds to the frequency span of the frequency range Df. Keys 10,27,39,41,42 and 43 in the initial state are always closed.

Received signal with combined linear frequency modulation and multiple phase shift keying (LFM-MPSK)

uc (t) Uc cos wct + пУ t2 + yK (t) -t.

where DC, We, p c, t and are the amplitude, initial carrier frequency, initial phase and signal duration:

Afg

y is the rate of change

thots inside the pulse;

D fg - frequency deviation; For kM, the phase component being manipulated displays the phase manipulation law in accordance with the modulating code M (t) (Fig. 5a). moreover, (p K (t) const at k e t (kM) ge and can change abruptly at t k.z s, i.e., at the boundaries between the elementary premises K 1.2, ..., M-1);

r3, N - the duration and number of elementary parcels from which the signal of duration t and (t and N g e) is composed:

from the output of the receiving antenna 3 through the broadband amplifier 4, it simultaneously enters the input of the amplitude detector 35 and the first input of the mixer 8. the second input of which supplies the voltage of the local oscillator 29 of a ramp frequency

Ur (t) Ur COS ((I) g t + meadow G 4 / g)

About t TP.

where Ur, Or, f r. Tn is the amplitude, initial frequency, initial phase and the repetition period of the local oscillator voltage;

yy -. - rate of change of the local oscillator frequency.

At the output of mixer 8, combinational frequency voltages are generated. Amplifier 9 only provides the intermediate frequency voltage 20

Unpl (t)

l-yr g

UnP COS «Wnpt + Л у, - + f K Р пр. О t Ги

where approx 1/2 Ki Uc Ur,

KI mixer transfer coefficient, t Pr m s - (D g - intermediate

frequency,

(About pr - r s - r g;

which is fed to the input of the detector 25. At the input of the frequency multiplier 46, an oscillation is generated by eight

ui (t) Unp wnpt + 8 l-yr t2-8 yr t2 + 8, 0 t ru

in which phase manipulation is already absent.

The width of the spectrum D f8 of the eighth harmonic of the signal is determined by the duration

and signal (Af8 -), while the width of MJ

the spectrum Afc of the received signal is determined by the duration of its elementary packets (Afc -). those. width

uh

spectrum of the eighth harmonic of the signal is N times smaller than the width of the spectrum of the input signal

Afc.

N

Therefore, by multiplying the frequency of the LFM-MPSK signal by eight, its spectrum is convoluted N times. This circumstance makes it possible to detect the LFM-MPSK signal even when its power at the input of the device is less than the power of noise and interference.

5

10

twenty

)

25

U

5

0

5

0

5

The spectral width A rV p-one m is measured using measure 47, the spectral width A f вось of the eighth harmonic of the signal is measured using a 4B meter. For example, U and Uc. proportional, and A fa, respectively, from the outputs of meters 47 and 48 of the spectral width are fed to two inputs of block 49 of comparison. Since U Ue. then a positive pulse is generated at the output of the comparator 40, which is fed to the input of the threshold unit 50, where it is compared with the threshold voltage Unop. The threshold voltage Unop is selected such that this level does not exceed random interference. The threshold voltage Unop is exceeded only when an LFM-MPSK signal is detected. When the threshold level Unop is exceeded, a constant voltage is generated in the threshold unit 50, which is supplied to the control input of the search unit 28, put it into stop mode, to the input of the delay element 26, to the control inputs of the keys 10 and 27, opening them. From this point in time, viewing the predetermined frequency range Df and searching for the LFM-MPSF signals stops for the time of visual analysis of the main parameters of the detected LFM-MPSF signal, which is determined by the delay time of the delay element 26.

The received LFM-MPSK signal from the second output of the broadband amplifier 4 simultaneously enters the input of the amplitude detector 35. and then through the video amplifier 37 to the first input of the comparison unit 38, the second input of which is supplied with the voltage from the output of the amplitude detector 36.

Serial-connected antenna 3, broadband amplifier 4. The amplitude detector 35 and video amplifier 37 form a detector receiver, and the series-connected antennas 3, broadband amplifier 4, mixer 8, the second input of which is connected to the output of the local oscillator 29, the intermediate-frequency amplifier 9 and the amplitude detector 36 form superheterodyne receiver. Since the total gain of the detector receiver when receiving LFM-MPSM signals on the main channel at a frequency (Oc is less than the gain of the superheterodyne receiver, a positive pulse is generated in the comparison unit 38, which is transmitted to the control input of the key 39, opening it.

When you stop viewing the specified frequency range Df (when stopped

block 28 search) of the amplifier 9 of the intermediate frequency voltage is allocated (Fig)

u ,, p2 (t) Unp cos ft) npt do t2 +

n - f K (t) -t / pr. O t Gu

which through public keys 39 and 10 is fed to the input of frequency multiplier 11 by eight. At the output of the frequency multiplier 11, a voltage is generated by eight

U2 (t) - Unp cos (8 ft) npt 8 l

+ 8 / 7pr). Oh t gee

which is extracted by the bandpass filter 12 and fed to the input of the frequency divider 13 by eight. At the output of the latter, a voltage is generated (Fig. 5c)

U3 (t) Unp COS Wnpt + Xyt. etc). About t TU

which is an LFM signal at an intermediate frequency and is extracted by a band-pass filter 14. This voltage is applied to the input of the frequency detector 5, at the output of which a video pulse is generated (Fig. 5d). the shape of which corresponds to the law of linear frequency modulation. The specified video pulse from the output of the frequency detector 5 is fed to the input of the differentiating circuit 6, the output pulse (Fig.5d) of which is supplied to the vertical electrode of the CRT 2, to the input of the differentiating circuit 7 and through the unipolar valve 40 to the control inputs of the keys 41 , 42 and 43, opening them.

Unipolar valve 40 transmits only positive pulses.

At the output of the differentiating circuit 7, short bipolar pulses are generated (Fig. 5e). Moreover, a positive short pulse is started, and a negative short pulse is closed by the generator 1 scan. The generated sawtooth voltage (Fig. 5g) is used as the scan voltage and is applied to the horizontal electrode of the CRT 2. A pulse is generated on the screen of the CRT 2 (Fig. 5d). the duration of which is proportional to the duration of r and the received LFM-MFMn signal, the amplitude is proportional to the rate of change of frequency inside the pulse, and the area of the oscillogram is proportional to the frequency deviation D fg (D fg y ty) of the received LFM-MFMn signal (Fig. 36).

The constant voltage from the output of the detector 25 through the public key 42 is applied to the vertical electrode of the CRT 33. A pulse (frequency mark) is generated on the screen of the CRT 33, the position of which on the horizontal scan uniquely determines the initial carrier frequency p from the detected LFM-MPSF signal ( Fig. Za).

The voltage from (0 (Fig. 5c) from the output of the band-pass filter 14 simultaneously enters the input of the adjustable delay element 24, at the output of which a voltage is generated

U / l (t) U3 (t -)) - Unp COG, (II np (t -)) + + у for it Г) 2 + (f) etc. O t ,, ,,.

This voltage is applied to the second input of the multiplier 15, the first input of which receives the received LFM-MPSM signal (Fig. 56) of the intermediate frequency from the output of the amplifier 9. A beating voltage is generated at the output of the multiplier 15 (Fig. 5z)

U 6l (t) U 6 COS (:% t 4 (p K (t) 1 / X, 0 t TU.

where U 6 1/2 K2 U2np,

K2 - transmission coefficient of the multiplier,

(B 2 put - beat frequency,

p - t -Jtytr - the initial phase of the beats; which is a phase-compensated signal at the beat frequency. Moreover, the beat frequency is determined by the rate of change of the signal frequency y and the value of the delay t.

The voltage U6i (t) is extracted by a hollow filter 16 and is fed to the input of the frequency multiplier 17 by eight, at the output of which a harmonic oscillation is generated

U62 (t) Ue cos (8 OJ6 t + 8 rb) 0 t ru.

The voltage U2 (t) is extracted by a narrow-band bandpass filter 18, and is fed to the input of the frequency divider 19 by eight, at the output of which a voltage is generated (Fig. 5i)

U63 (t) Ue cos (Mb t + / tg, 0 t t ,,

This voltage is a harmonic oscillation on the cpu bit; it is distinguished by the band phile swarms 20

narrow-band, and fed to the first pass of the Phase detector 21. The second input of which is supplied with voltage from the output of the generator 32 of the reference voltage

Uo (t) - Do cos (W0t f) 0

 2f

where do, do. f about the amplitude, frequency and initial phase of the local oscillator voltage.

If the indicated voltages differ in frequency or phase from each other, a control voltage is generated at the output of the phase detector 21. Moreover, the amplitude and polarity of this voltage depends on the degree and direction of the deviation of the beat frequency a b of the frequency o) 0 of the reference voltage generator 32. The control voltage is allocated by the low-pass filter 22 and, using the control signal generator 23, acts on the controlled delay element 24 by changing the delay value r so that the equality

oh, -2 meadow oh

A circular CRT 34 is used to visually evaluate the magnitude of the phase jumps D | / and the multiplicity m of phase manipulation of the received LFM-MPSK signal. Moreover, the circular scan is generated using the reference voltage generator 32, the frequency of which is maintained at the same beat frequency and% (MO ftJ6) using a phase-locked loop. The voltage U6i (t) (Fig. 4h) from the output of the band-pass filter 16 through the public keys 27 and 43 is fed to the input of the frequency detector 30, the output of which is formed by a sequence of short different-polarity pulses (Fig. Bq), the temporary position of which corresponds to the jerky signal phase changes (Fig. Bz).

The voltage Uo (t) from the output of the reference voltage generator 32 goes directly to the vertical electrode, and through the phase shifter 31 to 90 ° to the horizontal electrode of the CRT 34, forming a circular scan on its screen. The formed sequence of short bipolar pulses (Fig. Bq) from the output of the frequency detector 30 enters the CRT modulating electrode 34 and modulates its electron beam in brightness. On the screen of the CRT 34, an image is formed in the form of several bright dots located on a circle (Fig. 3bc). The number of points determines the multiplicity m

phase manipulation, the angular distance between them is equal to the magnitude of the phase jumps of the Ray received by the LFM-MPSM signal. If the frequency inequality is (5 f / h - a), the brightness marks will move around the circle with a difference frequency and the reliability of the visual assessment of the multiplicity m of phase manipulation and the magnitude of the phase jumps L / received by the LFM-MPSF

0 signal decreases sharply. To obsolete this, a phase locked loop system is used.

The delay time h l of the delay element 26 is selected such that

5 visually evaluate the main parameters of the received LFM-MPSK signal, observing the oscillograms on the CRT screens 2.33 and 34. After this time, the voltage from the output of the delay element 26 arrives

0 to the reset input of detector 25 (threshold block 50) and resets its contents to zero. In this case, the search unit 28 is put into tuning mode, and the keys 10 and 27 are closed, i.e. vehicle translation

5 to their original states. From this point in time, viewing the predetermined frequency range Df and searching for the chirp-MPSK signals continues.

If the following is found

0 LFM-MPSK signal operation of the device occurs in a similar way.

The operation of the device described above corresponds to the case of receiving LFM-MPSK signals on the main channel at a frequency

5 a) c (Fig. 4).

If the LFM-MPSK signal is received through the mirror channel at the frequency m3, then a negative rectangular pulse is generated at the output of the differentiating circuit b, which is not passed by the unipolar valve 40. The keys 41, 42, and 43 do not open a visual assessment of the main parameters of the received signal not produced.

5 If the LFM-MPSK signal is received on the first combinational channel at a) "1. then the overall gain of the detector receiver is greater than the gain of the superheterodyne receiver, no voltage is generated at the output of the comparison unit 38, and the key 39 does not open.

For a similar reason, the second Raman receive channel is also suppressed.

Claims (1)

5 Thus, the proposed device in comparison with the prototype provides increased reliability of the visual assessment of the main parameters of the received signal with combined linear frequency modulation and multiple phase manipulation. This is achieved by suppressing additional mirror and Raman reception channels. SUMMARY OF THE INVENTION An indicator device comprising an antenna in series, a broadband amplifier, a mixer, the second input of which is connected through a local oscillator to the first output of a sawtooth voltage generator, an intermediate frequency amplifier, a first key, a second input of a second connected to a detector output, a first frequency multiplier by eight, first bandpass filter, first eight frequency divider, second bandpass filter, first frequency detector, first differentiating circuit, sweep generator and burn on-off plates of the first cathode ray tube, vertically deflecting plates of which are connected to the output of the first differentiating circuit, a multiplier connected in series to the output of the intermediate-frequency amplifier, the second input of which is connected through the controlled delay element to the output of the second band-pass filter, the third band-pass filter , a second frequency multiplier by eight, a fourth band-pass filter, a second frequency divider by eight, a fifth band-pass filter, a phase detector, the second input of which The output of the reference voltage generator, a low-pass filter and a driver of the control signal, the output of which is connected to the second input of the controlled delay element, are connected to the output of the amplifier by an intermediate detector, the second input of which is connected to the output of the delay element, the sawtooth voltage generator and horizontally deflecting plates of the second electron beam tubes F ep ikkalo-deviation lOlJ me plisline which are connected to the output I will find the bodies, as well as connected in series to the output of the generator support 40 ° phase shifter and horizontally-deflecting poles. the length of the third cathode ray tube, the vertical deflecting plates of which are connected to the output of the reference generator voltage, and a modulating electrode through a series-connected second switch and a second frequency detector, connected to the outputs of the third band-pass filter and detector, characterized in that that, in order to increase the reliability of the visual assessment of the main parameters of the received signal, the first and second amplitude detectors, a video amplifier, a comparison unit, a unipolar valve, a third, fourth, fifth, and sixth keys are inserted into it, and the serial output of the broadband amplifier is connected in series first amplitude detector, video amplifier, comparison unit, second input which through the second amplitude detector is connected to the output of the intermediate frequency amplifier, and the third key, connected between the output of the intermediate frequency amplifier and the first input of the first key, the output of the first differentiating circuit is connected in series with a unipolar valve and a fourth key connected between the output of the scan generator and the horizontal deflecting plates of the first cathode ray tube, the fifth key is connected between the detector output and the vertical deflecting plates of the second cathode ray tube, the second the input of which is connected to the outputs of a unipolar valve l, between the output of the second key and the input of the second frequency detector, the neck of the second key is connected, the second input of which is connected to the output of the unipolar valve. flue. 2 6) l / s &# / & s COr Ct} C OfMn / IflMH TFMN ff ff s / n / # f + ff l FIA.Z  2®r this