Simultaneous polarization measurement method based on orthogonal intermittent sampling modulation radar signal

Abstract

The invention discloses a simultaneous polarization measurement method based on an orthogonal intermittent sampling modulation radar signal. The method comprises the steps that 1, a signal source generates linear frequency modulation signals and carries out radio frequency modulation; 2, AD sampling is carried out on the received two paths of polarized echo signals, then the signals are separated through an intermittent sampling emission time sequence, and four paths of polarized echo signals are obtained; and 3, pulse compression processing is carried out on the four paths of signals by using a matched filter of the complete linear frequency modulation signal. And 4, windowing of a pulse compression result is performed, and false peaks are removed to obtain polarization scattering matrix estimation of the target. According to the method disclosed by the invention, the emission of two paths of signals can be completed by using the same signal source in a switch switching mode, so that the hardware cost of the system is greatly saved; the two paths of intermittent sampling emission time sequence signals utilize diversity on a signal time domain to realize ideal signal isolation similar to time-sharing polarization measurement, and coherence of target polarization characteristic measurement can be ensured.

Description

【Technical field】 [0001] The invention belongs to the field of radar signal processing, and specifically relates to the processing technology of radar sending and receiving signals. Furthermore, it proposes a simultaneous polarization measurement method based on the principle of intermittent sampling for space targets. The simultaneous polarization measurement is realized by using the "time division polarization" in the pulse, and the realization method is simple. 【Background technique】 [0002] Polarization feature is one of the important characterization methods of target characteristics, which is of great significance to target recognition. For fully polarized radar, there are mainly two ways of simultaneous polarization and time-sharing polarization. Among them, the time-division polarization method alternately transmits two polarization signals in time division, and the interference problem between the two signals can be effectively solved by using time diversity. How...

AI Technical Summary

Problems solved by technology

However, due to the inconsistency of the time of different polarization channels, changes in the state of the target and the environment will bring about changes in the polarization scattering matrix, resulting in inaccurate measurements.

The simultaneous polarization method can effectively avoid this problem, but the simultaneous polarization method faces the design problem of orthogonal polarization waveforms. Currently, frequency-shifted pulse signals, positive and negative chirp signals, and quadrature phase-coded signals are commonly used. etc., but the orthogonality of the signal in actual use is difficult to guarantee, and the ideal orthogonal waveform does not exist

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