SU447639A1 - Low frequency phase meter - Google Patents

Description

The invention relates to a phase meris technique and can be used when late digital high frequency phase meters. The low-frequency phase meter contains a series-connected amplifier, mixer, electromechanical filter, second scooper, low-pass filter, driver, and heterodyne common to two channels, a coincidence circuit, a phase-locked loop SFAPC), consisting of a phase detector connected to the heterodyne input and a frequency divider connected to the input of the phase detector, the second frequency divider / additional divider, mixer and frequency meter. Such a device is characterized by a narrow band of capture and retention of the PLL system by the presence of parasitic settings, the complexity of tuning at low hours. The reference device in the known device uses quartz low 277 | 7) HZ. The purpose of the invention is to improve the operation of the PLL in the low-frequency region, to expand the capture and hold band, and to remove false settings. For this purpose, the 1st phase meter is equipped with a trigger in each channel connected between the driver output and the input of the coincidence circuit, as well as with a crystal oscillator, the output of which is connected to the third input of the coincidence circuit and the input of the first frequency divider, output connected to one of the additional inputs directly, and to the second through the second frequency divider, add electromechanical physegrom included between the inputs of the mixers of the second frequency converter and the input of the additional mixer, kr Moreover, the second input of the phase detector is connected to the output of the hybrid from the mixers of the first frequency converter. The quartz frequency is used as the reference frequency of the PLL system, and the second one is equipped with a summardine voltage, aoi, and if2 frequency If the device is equipped with a shaping circuit; The drawing shows a block diagram, I of the proposed phase meter. I The device contains amplifiers with AGC 1 and 2, mixers 3 and 4, local oscillator 5, electromechanical filters 6 and 7, sig; a PLL circuit consisting of a phase two vector 8, a second stage; transform. including mixers 9 and 10, and a heterodyne voltage shaping circuit consisting of a crystal oscillator 11,;, a mixer 12, frequency dividers 13 and 14, an electromechanical filter 15; The output part of the low-frequency phase meter contains low-pass filters 16 and 17, drivers 18, and 19, triggers 2O and 21, a coincidence circuit 22 and an electron-counting frequency meter 23. The device operates as follows. The low-frequency input signal is fed through amplifiers 1 and 2 to the inputs of the si: Cell 1 and 3i n 4. A heterodyne voltage is applied to the second inputs of the mixers. The frequencies of the heterodyne voltage are determined by the value of the first intermediate part, f g + f, and moreover, c, h1 1 nil the signal f must be greater than 2 nv1 signal. max 2 f). Voltage the maximum intermediate frequency produced by electromechanical filters 6 and 7 I is fed to the inputs of mixers 9 and 10, the I other inputs of which are applied to the heterodyne frequency voltage, Ij "jj, formatted by dividing the frequency of the quartz oscillator | 11, frequency dividers 13 and 14, followed by mixing in mixer 12 and filtering 15, to ensure the stability of the output frequency, the local oscillator 5 is covered by a phase locked loop, which includes a phase detector 8, at one of the inputs of which coherence is applied. : Mixer 3, and on the other - the voltage of the reference frequency f .. "removed from the dividend 14. The voltage of the second intermediate part of the monk comes from the mixture; Tel 9, 10 to filters 16 and 17, is filtered and fed to drivers 18 and 19 ,; triggers 20 and 21 of the coincidence circuit 22. In the locking scheme, a time interval is formed that is proportional to the phase shift at the input of the phase meter. The time interval is filled with the frequency of the crystal oscillator. 1 MHz and measured electronically. A countable frequency meter in the frequency ratio measurement mode. The subject matter of the invention is a frequency phase meter containing, in each of the two channels, successively connected an amplifier, a mixer, an electro-mechanical filter, a second mixer,: a low-pass filter, a driver, and also a local oscillator common to two channels, a coincidence circuit, a phase-locked loop frequency (PLL), consisting of a phase detector connected to the input of the heterodyne and frequency divider connected to the wahon. a phase detector house, a second frequency divider, an additional mixer and a frequency meter, characterized in that, in order to improve the operation of the PLL system in the low-frequency region, expanding the PLL acquisition and retention band, exclude; false settings, it is provided in each channel with a trigger connected between the output of the imaging device and the input of the link circuit, as well as a quartz oscillator, you-; the course of which is connected with the third input of the matching circuit and the input of the first frequency divider, the output connected directly to one of the inputs of the additional mixer, and the second through the second frequency divider, an additional electromechanical filter, between the inputs of the second frequency converter mixers and the additional input the mixer, in addition, the sec of the input of the phase detector is connected to the output of one of the mixers of the first transducer (receiver).

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