SU1335894A2 - Device for measuring phase shift in phase-shift-keyed signal - Google Patents

Abstract

The invention relates to a radio metering technique and can be used in radar where phase manipulated signals are used. The purpose of the invention is to increase the sensitivity of the device when measuring small phase shifts - achieved by introducing into the device a multiplier 8 an angle comprising phase shifter 9 by 90 °, quadrants 10, 12, 14 and 16, scaling multiplier 11 and adder 15 The device also contains intermediate frequency amplifier 1, multipliers 2 and 6, low-frequency filter 3, band-pass filter 5, narrow-band filter 7. The first multiplier 2 and filter 3 form a phase detector 4. Compared with the prototype in the proposed device provided a significant increase in sensitivity in the measurement of small phase shifts due to the fact that the measured phase shift in the received signal fazomanipuli- Rowan four times greater than that of the input signal. 1 il. S co 00 00 4 N

Description

The invention relates to a radio metering technique, can be used in radar and technology, where phase shift keyed signals (FMN) are widely used and is an improvement of the device according to the author. St. No. 924612.

The purpose of the invention is to increase the sensitivity when measuring small phase shifts.

The drawing shows a structural diagram of the |) of the device.

A device for measuring the phase shift in a phase-mapped signal contains an intermediate-frequency amplifier 1 connected in series, a first multiplier 2 and a low-pass filter 3. The multiplier 2 and the low-frequency filter 3 form a phase detector 4. The output of the first multiplier 2 is connected via a band-pass filter 5 to the first input of the second multiplier 6, the second input of which is connected to the output of the intermediate frequency amplifier 1, and the output through the narrow-band filter 7 is connected to the second input of the first multiplier 2. The output of the phase detector 4 is connected to the input of the angle multiplier 8. The angle multiplier 8 contains the phase shifter 9 connected in series by 90 °, the first quad 10, the multiplying multiplier 11, the second input of which is connected to the output of the second quad 12, the subtractor 13, the second input of which through the third quad 14 is connected to the output of the second quad 12, and the adder 15, the second input of which is connected via the fourth quadrant 16 to the output of the first quadrant 10. The output of the adder 15 is the output of an angle multiplier 8, the inputs of which are the combined inputs of the phase shifter 9 through 90 ° and the second quadrant 12.

The device operates as follows: The signal is an oscillation, the state and its of N elementary radio 11, the wavelengths of the same amplitude Vc, the duration of tee and frequency, adjacent to each other. Moreover, the phase of radio pulses can take one of the possible values of cp1, ..., cp „relative to the phase of the first HMHVjibca or relative to some reference sinusoid of the same frequency.

Received FMN signal at intermediate frequency

Uc (t) VcCOS wct + fc (1),

where Vs - is the amplitude and incomp 1, and (intermediate) signal frequency; v) to (1) is the manipulated component of the phase, reflecting the law of phase manipulation in accordance with the simulation code, with FC (1) const with Ктэ t - (К + 1) t

and may change abruptly at t Kt, i.e. on the borders between elementary premises (K 1, 2, ..., N);

te, N - the duration and number of elementary parcels, of which

A signal with duration Tc () is composed.

From the output of the intermediate frequency amplifier 1, the signal is fed to the input of the multiplier 2. The reference voltage from the output of the narrowband filter 7 LJo (t) Vocojct is applied to the reference input of the multiplier 2.

As a result of multiplying these voltages, the resulting oscillation 2 produces a resulting oscillation in the form of a set of voltages of sum and difference frequencies

Uy, (t) Vyic6s 2ioct + 94t) + 1С05фП1), where Ug is LKiVcVo;

Ki is the transfer coefficient of the transactor 2.

High frequency voltage

Ui (t) Vyicos 2coct + (fk {i),

which is a QPSK signal of twice the intermediate frequency, is separated by a bandpass filter 5 and is fed to the second input of the multiplier 6, to the first input of which from the second output of amplifier 1 of the intermediate frequency receives the received q QPSK signal. As a result of multiplying these voltages, the following resultant oscillation is formed at the output of multiplier 6

lJy2 (t) V5; 2cosa) ct Vv2cos 3wct + Ф (1), where UU2 -fKaVcVj;,;

5 Кз - multiplier transfer ratio 6.

The narrowband filter 7 from the oscillation Uy2 (t) separates the harmonic voltage of the intermediate frequency.

IJo (t) Vocostoct, 0 where Vo Vv2.

This voltage is used as a reference voltage and is applied to the reference input of multiplier 2.

Low frequency difference frequency voltage

 U2 (t) Vv | COSф ". (T),

proportional to the measured phase shift in the received QPSK signal, is allocated by a low-pass filter and is fed to the input of the multiplier 8 angle, which implements the Q function to multiply the angle in accordance with the expression

cos4a 6cos cc-sin a + sin a. At the output of the second quadrant 12, a voltage is formed

from (1) Vy, cosV (t).

5 This voltage is fed to the input of the third quadr 14, at the output of which a voltage is formed

U, (t) Vy, cosV (t).

At the same time, the voltage U2 (t) from the output of the low-pass filter 3 is fed to the input of the phase shifter 9 by 90 °, at the output of which the voltage U5 (t) Vxicos 9jfe (1) 4-90 ° -Vxisin9t (t) is formed. which is fed to the input of the first quad 10, the output of which forms a voltage

U6 (t), 5ш2f (1).

The voltages from (1) and U6 (t) are fed to the inputs of the scaling multiplier 11, the output of which is the voltage

U7 (t) 6U3 (t) -U6 (t) 6V iCosV (t) X X sinV (t) 10

Thus, the measured phase shift in the received phase-shift keyed signal is 4 times larger than that of the input signal. Thus, in the proposed device as compared with the known one, a significant increase in sensitivity is obtained when measuring small phase shifts.

Claims (1)

Invention Formula A device for measuring the phase shift in a phase-shift keyed signal by aut. St. No. 924612, characterized in that, in order to increase the sensitivity of the voltage U4 (-t) and U7 (t), 15 measurements of small phase shifts are received, to the inputs of the subtractor 13, at the output of which a voltage is formed U8 (t) U4 (t) - Urit (UjicosVit) - -6VJICosV (t)). The voltage Uelt) from the output of the first quad 10 is fed to the input of the fourth quad 16, the output of which forms a voltage U9 (t) VxisinV (t). The voltages Js (i) and Ug (i) are fed to the inputs of the adder 15, the output of which is the voltage Uio (t) U8 (t) + U9 (t) V j, cosV (t) -6Vx, cos V ( t) sinV (t) + VbsinV (t) At | 1С084fА (1). 20 25 A multiplier of angle is connected in series with the output of the phase detector and contains a phase shifter of 90 °, the input of which is connected to the output of the phase detector, and the output via the first quad with the first input of a scaling multiplier the second input of which is connected to the output of the phase detector output - with the first input of the subtractor, the second input of which is connected to the output of the second quadrant through the third quadrant, and the output - to the first input of the adder, the second input of which through the fourth quadrant of the connections with the output of the first squarer and an output is the output device. Thus, the measured phase shift in the received phase-shift keyed signal is 4 times larger than that of the input signal. Thus, in the proposed device as compared with the known one, a significant increase in sensitivity is obtained when measuring small phase shifts. Invention Formula A device for measuring the phase shift in a phase-shift keyed signal by aut. St. No. 924612, characterized in that, in order to increase the sensitivity when of five A multiplier of angle is connected in series with the output of the phase detector and contains a phase shifter of 90 °, the input of which is connected to the output of the phase detector, and the output via the first quad with the first input of a scaling multiplier the second input of which is connected to the output of the phase detector output - with the first input of the subtractor, the second input of which is connected to the output of the second quadrant through the third quadrant, and the output - to the first input of the adder, the second input of which through the fourth quadrant of the connections with the output of the first squarer and an output is the output device.