SU961459A1 - Receiver of secondary micropulse radar - Google Patents

Abstract

RECEPTION DEVICE OF SECONDARY MONO-PULSE RADAR, containing the first total-differential converter, the first input of which is the first input of the device, connected in series the first mixer, the first input of which is connected to the total output of the first total-differential converter, the first intermediate frequency amplifier, the intermediate frequency, the first mixer, intermediate frequency converter, the first output connector, the first total differential-difference converter the second mixer, the first input of which is connected to the differential output of the first total-differential converter, and the second silica gel-limiter-. the second frequency, the second total differential converter, the first and second inputs of which are connected co2 responsibly to the outputs of the first and second intermediate-frequency limiter amplifiers, the local oscillator, the first and second outputs of which are connected respectively to the second inputs of the first and second mixers, the first and second detectors, the outputs of which are the outputs of the device, characterized in that, in order to increase the accuracy of the measurement of the azimuth angle, the first phase manipulator is introduced into it, the first input of which is It is connected to the second input of the device, and the output is connected to the second input of the first sum-difference converter, the first linear filter whose input is connected to the sum. The secondary output of the second total-voltage transducer and the output are connected to the input of the first detector, connected in series to a second phase handler, whose input is connected to the differential output of the second total but a differential converter; the second is connected to the input of the second detector, 4 SP and shaper manipulation signal, in the input of which is connected to the second inputs of the first and second phase manipulators. -.

Description

The invention relates to radio engineering, in particular to radar, and can be used in air traffic control systems.

A secondary monopulse radar receiver is known, which contains the first sum-difference converter, the first input of which is the first input of the device, connected in series the first mixer, the first input of which is connected to the total output of the first total-difference converter, and the first amplifier of the intermediate frequency connected in series to the second mixer, the first input of which is connected to the differential output of the first total-mixed converter, and W Osoy usnlitel-limited. intermediate frequency carrier, second Total differential converter, the first and second inputs of which are connected respectively to the outputs of the first and second intermediate-frequency limiter amplifiers, first local oscillator and WTO: a swarm of which outputs are connected respectively to the second inputs of the first and second mixers, first and second detectors The outputs of which are the outputs of the device. However, the known receiver has large hardware errors due to the phase instability of the receiving channels. The purpose of the invention is to increase the accuracy of azimuthal fragmentation. To do this, a secondary monopulse radar receiver containing the first total-difference converter, the first input of which is connected to the device, is connected in series the first mixer, the first input of which is 9, is connected to the total output of the first total-differential converter, and the first or intermediate frequency limiter connected in series by a second mixer whose first input is connected to a differential output of a first total-differential converter, and a second intermediate frequency amplifier-limiter, a second total-differential converter whose first and second inputs are connected respectively to the outputs of the first and second amplifiers - limiters intermediate frequency you, local oscillator, the first and second outputs of which are connected respectively with the second inputs of the first and second mixes The first and second detectors. The outputs of the detectors are the outputs of the device a, the first phase handler is introduced, the first input of which is the second input of the device, and the 9th output is connected to the second input of the first total difference converter, the first linear filter whose input is connected with the total output of the second sum-difference converter, and the output - with the input of the first detector, connected in series to the second phase handler, whose input is connected to the difference output of the second total difference differential azovatel and a second linear filter, whose output is connected to the input of the second detector signal shaper manipulation, the output of which is coupled to second inputs of the first and second phase of the arms. The drawing shows the structural electrical scheme of the proposed receiver device. The receiver device contains the first total-differential converter 1, the first mixer 2, heterodgs 3, the first amplifier-limiter 4 intermediate frequency, the second mixer 5, the second amplifier-limiter 6, the second total-difference converter 7, the first linear filter 8, the first detector 9, the first phase manipulator JO, the second phase manipulator i1, the second linear filter 12, the second detector 13 and the shaping signal 14 manipulator uu receiving device monopulse secondary radar operates as follows. The total and difference signals are shifted relative to each other by 90, respectively, to the first and second inputs of the receiving device from the antenna-feeder radar system, respectively, and to the second input of the first total differential converter 1, the signal goes through the first. new phase manipulator, at the output of which the signal phase is periodically. changed to JSO. As a result of manipulating the phase of the difference signal, the outputs of the first sum-difference converter form, respectively, the sum and difference phase-shift keyed signals, which are converted by the corresponding mixers 2 and 5 and the local oscillator 3 into the phase-shift keyed signals at the exact frequency that then; are lined up and limited to the corresponding limiting amplifiers

596

4 and 6. During the transformation and amplification of the difference and total scaling lines by a copper, an unaccounted phase difference due to different phase phases is formed. By delays of different amplification channels and instability, so, of the time of phase delays of channels, which basically determine the instrumental error in measuring the azimuth angle. The second total differential converter 7 performs the inverse total differential difference signal, while at its differential output the signal acquires an additional amplitude modulationj due to phase instability of the receiving channels, and the greater the instability, the greater the amplitude modulation of the signal at the differential output e converter. Further, the phase-shift keyed signal of the second sum-difference converter passes the second phase handler 1, which operates synchronously with the first phase handler 10, is demanipulated. Tov. is transformed from a phase-manipulated signal into a smooth continuous signal modulated only by amplitude, whose spectrum narrows to a value equal to the original signal spectrum, while at the first phase shift the signal spectrum expands, which leads to a worse signal-to-noise ratio. ; After filtering the signal with a linear filter consistent with the spectrum of the signal, recovery takes place. ne {) initial signal / ratio

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/noise. Then cnnai is detected de-. tector 13, the time constant of which is significantly longer than the manipulation period, due to which the signal is not only detected but also averaged, while the amplitude of the average pulse value at the detector output is defined as the arithmetic average

Q is the signal amplitude value for the duration of all periods of phase manipulation in a pulse, and the magnitude of re-. the resulting error in measuring the pulse amplitude is practically independent of -,. of the additional phase angle due to the phase instability of the receiving channels

Bandwidth of individual functional units of the receiving device

0 are selected according to the spectra of the transmitted signals. Experimental verification of the proposed receiver with a carrier signal frequency of 740 MHz, a pulse width of 1 µs and a pulse frequency of 500 MHz, the phase manipulation frequency of 20 MHz, the bandwidth of the amplifiers of the frequency range of 60 MHz and

0 band of 10 MHz linear filters,

The technical and economic effect of the proposed receiver is to reduce the requirements for the phase instability of the receiving devices during their manufacture without reducing the accuracy of the azimuth angle measurement when the secondary mono-impulse radar operates.

Claims (1)

RECEPTION DEVICE OF SECONDARY MONO-PULSE RADAR, containing the first total-differential converter, the first input of which is the first input of the device, connected in series the first mixer, the first input of which is connected to the total output of the first total-differential converter, and the first intermediate-frequency amplifier, connected in series to the second mixer the mixer, the first input of which is connected to the differential output of the first total-differential converter, and the second amplifier -ogranichitel prome-. frequency per second, the second total differential converter, the first and second inputs of which are connected by co2 responsibly with the outputs of the first and second intermediate-frequency amplifiers, the local oscillator, the first and second outputs of which are connected respectively to the second inputs of the first and second mixers, the first and second detectors, the outputs of which are the outputs of the device, characterized in that, in order to improve measurement accuracy azimuth angle, the first phase manipulator is entered into it, the first input of which is the second input of the device, and the output is connected to the second input of the first total-difference converter, a second linear filter, whose input is connected to the sum-> standard output of the second total-differential converter, and an output to the input of the first detector, connected in series to a second phase manipulator, whose input is connected to the differential output of the second total-differential converter, second linear filter, the output of which is connected to the input of the second detector, and the shaper of the manipulation signal, the output of which is connected to the second inputs of the first and second phase manipulators, 5TS 961459 The invention relates to radio engineering, in particular to radiolocation, and can be used in air traffic control systems.