RU1789938C - Analyzer of spectrum of electric signals - Google Patents

Abstract

Summary of the invention: the analyzer contains a laser radiation source 1 with two generation frequencies, a radiation beam former 2, a phase element 3 with an even number of half-waves of one frequency and an odd another, a prism of total internal reflection 4, on the reflective face of which a film of magneto-optical material 5 (MOM) is located , a second phase element 6, a polarizer 7, a Fourier lens 8, and a photographic recorder 9 located in series along the light beam. With the MOM film, magnetic tape 10 is in contact with the drive unit 11 and the recording unit 12. The recording unit is the electrical input of the analyzer; The difference in the generation frequencies is less than the resolution of the analyzer. After passing through the first phase element, the laser generation frequencies acquire orthogonal polarizations. During diffraction by MOM, orthogonal polarizations have inverse amplitude-frequency characteristics (AFC). When the diffracted rays are combined with orthogonal polarizations, the frequency response is equalized. 1 ill.

Description

The invention relates to techniques for analyzing the spectrum of electrical signals and may find application in electronics, computing and other fields of technology.

The purpose of the invention is to increase the accuracy of measurements by equalizing the amplitude-frequency characteristics (AFC).

An optical circuit of the analyzer is presented at the .ertage: 1 - laser light source: 2 - light beam former; 3 - phase element; 4 is a prism of total internal reflection, on the reflective face of which a film of magneto-optical material (MOM) 5 is located; 6 - second phase element; 7 - polarizer; 8 - Fourier lens; 9 - photo recorder (located sequentially along the beam of light),

The device operates as follows. . . .

The studied signal is recorded on the magnetic tape 10 by the recording unit 12, and the drive unit 11 pulls the tape 10 under the MOM 5 film. The scattering field of the waveform induces a magnetization structure similar to the frame signals on the MOM 5 films. The light of the laser source 1 is expanded by the shaper 2 and passes through the phase element 3. At the output of the phase element 3, two parallel beams of light are formed, differing in frequency and polarization from each other. The polarization of one of the frequencies lies in the plane

the fall, and the polarization of the second is perpendicular to the plane of the fall. After passing through the total internal reflection prism 4, these beams enter the MOM 5 film and diffract on the induced magnetization structure. The diffracted rays exit the prism 4 and enter the second phase element 6, where the polarization of the zero-order rays is restored, and the polarizations of both frequencies of light become parallel. Then, the rays of light fall into the polarizer 7, which transmits rays of higher diffraction orders and does not pass zero. After passing through the Fourier lens, the diffracted beams are collected in the focal plane and form the spectrum of the electrical signal. Photorecorder 9 reads the resulting spectrum. Since the read signal is the sum of two rays with orthogonal polarizations, the intensities of which change in antiphase with a change in the electric frequency, the total frequency response of the MOM film will be equalized and thereby the measurement accuracy will be improved. In addition, upon diffraction of the above two laser generation frequencies, the induced array will not resolve the edi frequency, and there will be no 0 separation of the diffracted beams into two and, accordingly, no false signal, which will also increase the measurement accuracy.

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SUMMARY OF THE INVENTION An electric signal spectrum analyzer consisting of a laser radiation source, a beam shaper, a total internal reflection prism, on the reflective face of which is a magneto-optical material (MOM) film, a polarizer, a Fourier lens, and a photographic recorder arranged in series along In the course of the beam of the set, the magnetic tape with the drive and recording unit in contact with the MOM, the recording unit is the electrical input of the analyzer, the photorecorder is the output.

Compiled by Editor G. Bielska Tehred M. Morg

characterized in that, in order to increase the measurement accuracy by equalizing the amplitude-frequency characteristics, it additionally contains two phase elements located between the laser and the MOM and between the MOM and the polarizer, the laser is capable of generating two frequencies, the phase difference of the light path between polarization is equal to the even number of half-waves for one frequency and odd for the other; the difference in the laser generation frequencies is less than the maximum resolution of the analyzer.

Proofreader: M. Keretsman