SU1256131A1 - Harmonic generator - Google Patents

Abstract

The invention relates to radio engineering. The purpose of the invention is to increase the reliability of the harmonic number setting while decreasing the output frequency step. The generator contains two stable frequency oscillators (RNG) 1.5, frequency multiplier 2, generator 3 with phase-locked loop (PLL), harmonic number indicator (ING) 4, switch 6, mixer 7, two low-pass filters 8, 9, two formers 11 pulses, the counter 12, the memory block 13 and the control block 14. The generator operates in two modes: generation and installation of the required harmonic number. In the generation mode, the RNG 1 signal goes through a switch 6 and a frequency multiplier 2 to the phase detector 17 of the PLL circuit of the generator 3, where when the Gunn generator 15 is tuned, its frequency is captured at one of the spectrum frequencies nFi, the number of which is to be determined. In the mode of setting the required harmonic number, at the command of the control unit 14, the switch 6 simultaneously operates, and the controlled proportional-integrating filter 19 of the PLL circuit goes into the operation mode with a greater constant T time than the time constant Ti in the generation mode, which leads to “Memorizing the frequency of the 15 Gann oscillator for the time of the absence of oscillations nFi at the output of the multiplier 2 frequencies. The readings of counter 12 are reset and in the memory unit 13 the previous harmonic number value is erased. When switching on the RNG 5 with the frequency Rd, the difference signals p / P.-F, / and p / p2-PI /, converted to LPF 8, 9 and formers 10, 11 pulses are fed to the counter 12, which performs frequency division and forms the binary the number n memorized in block 13 of memory and indicated in ING 4. 1 sludge. F (L to SP O) 00

Description

The invention relates to radio engineering and can be used in frequency synthesis devices in frequency division multiplex communication systems.

The purpose of the invention is to increase the reliability of the harmonic number setting while decreasing the output frequency step.

The drawing shows a structural electrical circuit of a harmonic generator.

The harmonic generator contains the first stable frequency generator (RNG), a frequency attenuator 2, the generator 3 with phase-locked loop, 4 harmonic number indicator, the second RNG 5, switch 6, mixer 7, the first low-pass filter 8 (LPF), the second The low-pass filter 9, the first pulse shaper 10, the second pulse shaper 11, the counter 12, the memory block 13, the control block 14. The generator 3 with the phase-locked loop at the same time contains a Gunn generator 15, a power coupler 16, a phase detector 17, a DC amplifier 18 and a controlled proportional-controlled filter 19.

The harmonic generator operates in two modes - generation and in the mode of installation of the required harmonic number.

In the generation mode, the signal of the first RNG 1 with the frequency FI through the switch 6 is fed to a frequency multiplier 2, the output of which forms the harmonic spectrum nFi () frequency F.

Harmonics from the output of the multiplier 2 frequencies are fed to one of the inputs of the phase detector 17, which is part of the phase-locked loop circuit to the second input of the phase detector 17, through a TUBE 16 coupler, part of the 15 Gann generator signal. When tuning the 15 Gann generator, its frequency is captured at one of the frequencies of the spectrum whose number is to be determined.

In the mode of setting the required harmonic number, at the command of the control unit 14, the switch 6 simultaneously operates, and the controlled proportional-integrating filter 19 switches to the operation mode with a longer time constant T2 than the time constant T: in the generation mode.

A controlled proportional-integrated filter can be made in the form of an integrated circuit with a series of resistors connected in series, a capacitor and a controlled resistor with two discrete resistance values (for example, a field effect transistor). An increase in the time constant of the phase-locked loop circuit leads to “memorizing the frequency of the 15 Gann oscillator for the time of no oscillation with the frequency nFi at the output of the multiplier 2 frequencies. The readings of counter 12 are reset and in block 13 of the memory, the previous harmonic number value is deleted. For a period of time TZ, the 15 Gann oscillator frequency remains the same nFi and its signal is fed to one of the inputs of the phase detector 17, to the other input of the signal nF spectrum from the second RNG 5, having a frequency F close to FI. At this time, the phase detector 17 functions as a mixer, and a differential frequency signal is generated at its outputs.

f nF2-nF | n / F2-Fi / nF,

whereas at the output of the mixer 7, the difference frequency signal F: / F2FI / is constantly allocated.

The output signals of the difference frequencies f and F from the outputs of the phase detector 17 and the mixer 7 through the first and second low-pass filters 8 and 9 are fed to the first and second formors, bodies 10 and 11, respectively. These drivers 10 and 11 provide amplification, limitation, amplitude detection and the formation of rectangular pulses with frequencies nF and F, respectively. Pulses with frequency nF arrive at the counting input of the counter, and pulses with frequency F reach the setting input of the previously zeroed counter 12, which There is no function to divide the frequency nF by F, and a binary number n is generated at the bit outputs of the counter, which is stored in memory block 13 and fed to indicator 4. The latter can be digitally decoded rum at the input that converts the binary code of the n-number harmonics, for example, into the seven-segment code of the indicator 4. After the time has elapsed, the control unit 14 changes the command to the original one and the 15 Gann generator continues to operate in the normal capture mode at the previous frequency nFi, i.e The process of setting the required frequency does not violate the mode of the 15 Gann generator.

Thus, due to the freedom of variation of the ratio F2 / F | It is chosen to reliably determine the harmonic number FZ frequency of the second RNG 5 at any grid density nFi, generated stable frequencies at an arbitrarily high output frequency of the harmonic generator.

Claims (1)

Invention Formula A harmonic generator containing the first stable frequency generator, a frequency multiplier, a generator with a phase-locked loop, and a phase-locked loop containing a phase detector and a proportional-integrating filter, as well as a harmonic number indicator, the output of the frequency multiplier connected to the phase detector that, in order to increase the reliability of the harmonic number setting while decreasing output frequency grid spacing, between the output of the phase detector and the harmonic number indicator input, the first low-pass filter, the first pulse shaper, the counter, the memory block, the second stable frequency generator, the second low-pass filter and the second shaper are entered into it pulses, a control unit and a switch, the output of which is connected to the input of a frequency multiplier, and the first and second inputs of the switch are connected to the outputs of the corresponding editor N. Margol ina Order 4833/54 VNIIPI USSR State Committee for inventions and discoveries 1 13035, Moscow, Zh-35, Raushsk nab. 4/5 Branch PPP "Patent, Uzhgorod, st. Project, 4 but the first and second stable frequency generators, the output of the second pulse generator is connected to another input of the counter, the output of the first stable frequency generator is connected to another input of the mixer, the control inputs of the memory unit and the switch are combined and connected to the output of the control unit, while The integrating filter is designed as a controlled proportional integrating filter, the control input of which is connected to the output of the control unit. Compiled by Yu. Kovalev Tehred I. VeresKorrektor E. Roshko Circulation 816 Subscription