SU543127A1 - Device for pulse-phase-locked loop - Google Patents

Description

one

The invention relates to radio engineering and can be used in radio transmitting exciters to form sequences of coherent radio frequency modulated radio frequency signals with a high linearity of the law of frequency variation.

A device for pulse-phase-locked loop is known, comprising a linear frequency modulated oscillator and a series of gated comparison circuits in which an error signal is generated, proportional to the frequency deviations from linear law 1.

Odiako this device has an increased level of frequency distortion caused by transient processes in gated circuits.

The closest technical solution is a device for pulse-phase auto-tuning of the frequency, containing a reference oscillator connected to a generator with linear frequency modulation through three circuits, the first of which contains serially connected video pulse former, phase detector, low-pass filter and signal amplifier errors, the second is the sequence of the connected synchronizer and the modulator, and a third is the sequence of the connected frequency multiplier.

a phase detector connected to the output of a linear frequency modulated oscillator and a gated amplifier whose input is connected to the output of synchronizer 2.

However, this device has significant residual frequency distortion. In order to reduce the residual frequency

distortions in the proposed device for a phase-phase self-tuning frequency generator output with linear frequency modulation is connected to the phase detector of the first circuit through n series-connected frequency converters, where n 1, 2, 3 ..., the second inputs of which are connected to the output of the scooter generator.

The drawing shows a structural electrical circuit of the device for an imulse-phase self-tuning frequency for the case of a double frequency conversion ("2).

The device contains a reference generator 1, connected to the generator 2 with linear

frequency modulation (chirp) through three circuits, the first of which contains a serially connected driver of 3 video pulses, a digital detector 4, a filter of 5 frequency and an error signal amplifier,

the second is a serially connected synchronizer 7 and a modulator 8, and a third is a frequency serially connected multiplier 9, phase detector 10, which is connected to the output of generator 2, and a gated amplifier I, whose control input is connected to the output of synchronizer 7. The output of generator 2 is connected to the phase detector 4 of the first pepi through two series-connected frequency converter 12 and 13, the second inputs of which are connected to the output of the reference generator 1, and the frequency converter 12 consists of a mixer 14, a multiplier 15 frequency and bandpass amplifier 16, and the frequency converter 13 is from mixer 17, frequency multiplier 18, and bandpass amplifier 19.

The device works as follows.

The signal generated by the generator 2, and is fed to the input of the mixer 14 of the first frequency converter 12. Harmonic voltage from frequency multiplier 15 is applied to the second input of this mixer, the frequency of which

/ 1 / „+ D // 2,

where / n - the initial frequency of the line-frequency-modulated signal (chirp);

A / - frequency deviation.

The converted signal, the frequency of which varies according to the Y-shaped law, is amplified in the bandpass amplifier 16 and is fed to the input of the mixer 17 of the second frequency converter 13. To the second input of this mixer comes the voltage from the multiplier 18 frequency, the frequency of which

.

After the second conversion in mixer 17, the signal with 1 frequency modulation, the maximum frequency of which is four times less than the frequency deviation of the original chirp signal, is amplified in the amplifier 19 and is fed to one of the inputs of the phase detector 4.

In the general case, two transformations will be used ne, and n, then at the output of the "-TH converter, the maximum frequency of the converted chirp signal is

/ m.p-D //2.

In this case, the frequency of the harmonic voltage supplied to the mixer of the lth frequency converter from the corresponding multiplier, the dollar to have the value

f Af / 2,

and the required duration of the reference video pulses.

required for known devices 2 times and should be

t ;, 2,.

In order to ensure the frequency adjustment of the signal with the A / V deviation and the minimum duration of the standard video pulses, which can be rea; 1, the required number of frequency conversions is based on the ratio

(T:, A /).

The reference video pulses from the video pulse maker are fed to the second input of the phase detector 4, from the output of which the error signal through the low-pass filter and the error signal amplifier and the output signal

to the input of generator 2 and compensates for frequency deviations from the linear law.

Claims (2)

1. Pateit USA N ° 3621450, cl. 331-10, publ. 11/16/91. 2. Campbell B.D. Radar with coherent linear FM, which has ultra-high resolution, “Foreign Radio Electronics, 1971, No. 4 (butrotype).