SU1378056A1 - Shf adjustable generator - Google Patents

Abstract

The invention relates to radio engineering and provides increased frequency stability when expanding the range of tunable frequencies. The RF tunable generator contains a master oscillator 1, frequency multipliers (UF) 2.4 and 14, directional taps 3 and 5, phase modulator (FM) 6 , mixer 7, band pass, filter 8, intermediate frequency amplifier 8, error sensor in the form of a phase detector (PD) 10, operational amplifier 11 controlled by PV 12 and sawtooth generator 13. UCh 4 and 14 have a multiplication factor of n, and UCh 2 - multiplication factor of ap. With UCh 14, a reference signal for PD 10 is generated from the signal of the master oscillator 1. The output signal of the microwave generator is generated by UCh 2 and 4 and FM 6. The generator 13 and the controlled FB 12 provide, in the case of frequency tuning of the master oscillator J, a synchronous change in the frequency of the signal fed to mixer 7, Mixer 7, band-pass filter 8, amplifier 9, and PD 10 provide a selection. The signal of the parasitic frequency deviation of the phase of the output signal occurring in the elements of the microwave generator, except for the master oscillator 1, the error signal from the output of the PD 10 is used in FM 6 to suppress the parasitic frequency deviation of the output signal. 1 il. i (L

Description

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11378056

The invention relates to radio engineering and can be used in radio receiving and radio transmitting devices.

The aim of the invention is to increase the frequency stability while expanding the range of tunable frequencies.

The drawing shows a structured electrical circuit of an ultrahigh-Q-value (UHF) tunable generator.

The microwave tunable oscillator contains a master oscillator which is on. the control input of the generator 13 receives a clock signal.

Thus, a sawtooth voltage of a constant amplitude and with a frequency fо varying depending on the frequency tuning f of the master oscillator J is fed to the control input of the controlled phase shifter 12, if the phase change of the high-frequency signal with the frequency mfo fed to the control input controlled phase shifter 12, is equal to

nerator 1, the first multiplier 2 is often 15 21 (N (where N ± 1, ± 2,. ,,,)), the part of the input of which receives a synchronizing signal at the control input of the generator 13.

Thus, a sawtooth voltage of a constant amplitude and with a frequency fо varying depending on the frequency tuning f of the master oscillator J is fed to the control input of the controlled phase shifter 12, if the phase change of the high-frequency signal with the frequency mfo fed to the control input controlled phase shifter 12, is equal to

you, the first directional coupler3 the second multiplier 4 frequencies, the second directional coupler 5, the phase modulator 6, the mixer 7, the band-pass filter 8, the amplifier 9 intermediate frequency, the error sensor, made in the form of the phase detector 10, the operation- 1CHONNY amplifier And, controllable phase shifter J2, generator 13 sawing voltage and the third multiplier J4 frequency.

Microwave tunable generator operates as follows.

The signal with the frequency f from the output of the master oscillator 1 is fed to the first multiplier 2 connected in series with the multiplier sn and the second multiplier 4 with multiplication factor XI. Then the signal with frequency mnf is fed to the output through phase modulator 6. A part of the signal power with the frequency mnf is branched off by the second directional coupler 5 and is fed to the second input of the mixer 7. The signal whose frequency is formed as follows is sent to the first input of the mixer 7.

The part of the signal power with the frequency rofo is coupled by the first directional coupler 3 and is fed to the signal input of the controlled phase shifter 12, the output of which is connected to the first input of the mixer 7. The controlled phase shifter 12 is electrically tunable (controlled) by a linear microwave phase shifter with a phase change of glad,

The control input of the controlled phase shifter J2 is affected by a sawtooth signal from the output of the generator 13. The period of the sawtooth voltage is related to the frequency of the driving oscillator 1, s

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that at the output of the controlled phase shifter 12 is shifted by the value of dG, In the simplest case I «+1, Af f. In that

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then dg g. And in this case, the first input of the mixer 7 is affected by the signal with frequency mf + fa. Mixer 7 is set to select the output of the intermediate frequency, totah Г „n (mf, + f) -mnf nf, which goes to band-pass filter 8 with a center frequency nf and a band of 2uF, where D F is the maximum frequency tuning range of the master oscillator 1 relative to the nominal value f. The signal is further amplified by amplifier 9 and fed to the second input of the phase detector 10. The first input of the phase detector 10 receives a signal from the third multiplier 14, the multiplication factor n of which is equal to the multiplying factor of the second multiplier A. Thus, when the frequency of the master oscillator 1 is tuned to The detector 10 always receives signals of the same frequency.

In the presence of parasitic frequency deviation (phase) of the output signal, the signal from the output of the second directional coupler 5 also has parasitic frequency (phase) deviation. After conversion in the mixer 7, the output signal of the phase detector 10 has a variable component depending on the nature of the parasitic phase frequency deviation arising in the elements of the microwave generator, besides the master oscillator J.

The signal arriving at the first input of the phase detector 10 through the third multiplier 14 is a reference, against which the phase comparison takes place. The variable component of the output signal of the phase detector

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pa 10 is amplified by an operational amplifier Pi is fed to the control input of phase modulators 6 which provides synchronous demodulation of the parasitic frequency deviation (phase) of the output signal of the super high frequency oscillator. In this case, the parasitic frequency deviation of the output frequency (phase) of the super high frequency tunable generator all, the frequency range in which it is tuned.

Claims (1)

Invention Formula A microwave tunable oscillator containing a Tenbko series connected master oscillator and the first frequency multiplier, the second frequency multiplier, the first directional coupler, the mixer, the intermediate frequency amplifier, the error sensor, and the phase modulator, in order to detector, the control input of the sawtooth generator and the input of the third multiplier are interconnected and connected to the output of the master oscillator; the input, the first and second outputs of the first directional coupler are connected respectively to the output of the first frequency multiplier, to the input of the second multiplier the input of the controlled phase shifter, the output of which is connected to the first input of the mixer, the input, the first and second outputs of the second directional antenna, are connected respectively to the output the second frequency multiplier, with the input of the phase modulator and the second mixer input, the output of which is connected to the input of the bandpass filter, the first and second inputs of the phase detector are connected to the outputs of the third frequency multiplier and the intermediate frequency amplifier, the input of which is connected to the output of the bandpass filter, input and the output of the operational amplifier is connected respectively to the output of the phase detector and the control input of the phase module of the frequency stability top module when the tuning range is expanded frequency generator, a sawtooth voltage generator, controlled by a phase rotation n Pa, whose output is an output, a third frequency multiplier, super-high-frequency tunable filter, a second directional oscillator, and a generator output coupler and operational amplifier, a sawtooth voltage The sensor is connected to the error sensor in the form of the control input of the phase shifter. 0 five 0 five detector, the control input of the sawtooth generator and the input of the third multiplier are interconnected and connected to the output of the master oscillator; the input, the first and second outputs of the first directional coupler are connected respectively to the output of the first frequency multiplier, to the input of the second multiplier the input of the controlled phase shifter, the output of which is connected to the first input of the mixer, the input, the first and second outputs of the second directional antenna, are connected respectively to the output the second frequency multiplier, with the input of the phase modulator and the second input of the mixer, the output of which is connected to the input of a bandpass filter, the first and second inputs of the phase detector are connected to the outputs of the third frequency multiplier and the intermediate frequency amplifier, the input of which is connected to the output of the bandpass filter, input and the output of the operational amplifier is connected respectively to the output of the phase detector and the control input of the phase module n Pa, the output of which is the output of a super high-frequency perestroika generator, and the output of the sawtooth generator is connected to the control input of the phase shifter.