SU508750A1 - Device for measuring the width of signal spectra - Google Patents

Description

one

The invention relates to the field of radio measurements and can be applied to automatically measure the width of the spectra of radio signals.

The known device for measuring the width of the spectra of signals, containing its serially connected panoramic local oscillator, a mixer whose second input is connected to the device input, an intermediate frequency amplifier, a detector, a video amplifier, a threshold circuit and a pulse counter, does not provide the required measurement accuracy.

The aim of the invention is to improve the accuracy of measuring the width of the spectrum of radio signals.

The goal is achieved in that a serially connected pulse generator, a manipulated generator, an additional mixer, a filter and a bend detector are entered into the known device, the second input of the additional mixer is connected to the output of a nanorodine heterodyne, and the output of the detector is curved, connected to the input of the pulse counter.

The drawing shows a functional diagram of the device, where 1 is a mixer, 2 is a panoramic local oscillator, 3 is an intermediate 4acTOTfji amplifier, 4 is a detector, 5 is a video amplifier, 6 is a threshold circuit, 7 is a pulse counter, 8 is an additional mixer, 9 is

manipulated oscillator, 10 - impulse generator, 11 - filter, 12 - detector bend around it.

The device works as follows. The signal under study is fed to the mixer 1, for example, from the output of the receiver, which is previously normalized by the spectrum. At the same time, the second input of the mixer 1 receives the voltage of the frequency-tuned panorama local oscillator 2. The intermediate frequency signal is fed to the input of the narrowband TRF 3 path, performed as a filter loop (resonator) during the sequential analysis of the signals. After detecting with the aid of the detector 4 and amplifying with the video amplifier 5, the voltage, characterizing its spectral density, arrives at the threshold circuit 6, which is triggered at certain predetermined levels (for example, 0.5 of the maximum). As a result, at the output of the threshold circuit 6, a strobe is formed corresponding to the restructuring time of the panoramic local oscillator 2 within the width of the signal spectrum. This strobe is fed to the control input of the impulse counter 7, operating only on the strobe interval. Simultaneously, the frequency of the voltage of the panoramic local oscillator 2 is fed to the mixer 8. Pa the second input of this mixer

Claims (2)

Impulse generator 9 is applied, which is manipulated in amplitude by impulses of impulse generator 10. With a short duration of manipulating impulses, a fairly uniform amplitude of frequency marks within the tuning band of the local oscillator can be obtained. Thus, setting the following frequency and duty ratio of the manipulating pulses of the generator 10, we obtain the necessary discreteness and uniformity of the frequency marks. The filter 11, turned on at the output of the mixer 8, extracts the frequency marks that appear at the output of the filter successively as a result of the restructuring of the panoramic local oscillator. 2. Filter 11 is tuned to the total or differential frequency formed by the midrange frequency of the tuning tuning of the panoramic heterodip 2 and the carrier frequency of the manipulated oscillator 9. The envelope detector 12 selects the envelope of the frequency marks appearing at the output of the pulse counter 11 7. The counter, as indicated, is controlled by a signal from the output of the threshold circuit 6. Therefore, the number of frequency marks recorded by the counter determines the width of the spectrum of the signal under study. An apparatus for measuring the width of the spectra of signals, comprising a series-connected panoramic local oscillator, a mixer whose second input is connected to the device input, an intermediate frequency amplifier, a detector, a video amplifier, a threshold circuit, and a pulse counter, characterized in that a series-connected pulse generator, a manipulated generator, a secondary mixer, a filter and an envelope detector are introduced into it, with the second input of an additional esitel connected to the output panoramic oscillator, and the output of the envelope detector connected to the input of the pulse counter.