SU1518864A1 - Frequency divider - Google Patents

Abstract

The invention relates to radio engineering and can be used in frequency synthesizers. The purpose of the invention is to reduce the time to establish output fluctuations. The frequency divider contains a frequency mixer 1, a frequency multiplier 3, a band-pass filter 4. The goal is achieved by introducing synchronized r-band 2, an amplitude limiter 5, and a frequency detector 6. At the time the power is turned on, the frequency divider is set to oscillate the input signal, which reduces the installation time of the oscillations and increases the reliability of operation in comparison with the known frequency dividers. 1 il.

Description

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The invention relates to radio engineering and can be used in frequency synthesizers.

The purpose of the invention is to reduce the time to establish output fluctuations.

The drawing shows a structural electrical frequency divider circuit.

The frequency divider contains a frequency mixer 1, a synchronized generator 2, voltage controlled, a frequency multiplier 3, a band-pass filter 4, an amplitude limiter 5, a frequency detector 6.

The frequency divider works as follows.

When the power is turned on, the synchronized generator 2 begins to produce periodic oscillations at a frequency determined by the voltage at the control input, which, after multiplying N times the frequency in multiplier 3, passes through a band-pass filter 4 that suppresses unwanted spectral components, to the second input of the mixer 1 sec. The input signal is fed to the first input of the mixer 1, and the signal with the differential frequency is fed to the synchronization input of the synchronized generator 2, which, by capturing the signal, sets the frequency of the output signal of the frequency divider equal to the frequency of the signal at the output of the mixer 1, and :

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where Fg and F respectively the frequencies of the input and output signal of the frequency divider At the same time, the signal from the input of the frequency divider passes through the limiter 5, eliminating the amplitude instability of the input signal, to the frequency detector 6, whose central frequency corresponds to

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average frequency of the working range. In this case, a constant voltage proportional to the frequency deviation of the input signal appears at the output of the frequency detector 6, which is fed to the control input of the synchronized oscillator 2 and performs a coarse frequency range setting. Thus, at the moment the power is turned on, oscillations are set in the frequency divider, the frequency of which is rigidly fixed to the frequency of the input signal, thereby reducing the time for establishing oscillations and ensuring reliable operation in comparison with the known regenerative frequency dividers.

Claims (1)

Invention Formula A frequency divider, containing a frequency mixer, the first input of which is an input of a frequency divider, serially connected frequency multiplier and a band-pass filter, the output of which is connected to the second input of a frequency mixer, characterized in that, in order to reduce the output oscillating time, synchronized voltage controlled oscillator whose output is a frequency splitter output, serially connected amplitude limiter and frequency detector that are connected between the first input the mixer and the control input of a synchronized oscillator controlled by voltage, while the output of the frequency mixer is connected to the synchronization input of the synchronized oscillator controlled by voltage, the input of the frequency multiplier is connected to the output of the synchronized oscillator controlled by voltage.