Accurate frequency measurement method for high-dynamic weak MPSK signal

Abstract

The invention discloses an accurate frequency measurement method of a high-dynamic weak MPSK signal, and aims to provide an accurate frequency measurement method capable of adapting to a high-dynamicweak signal complex scene. The method is realized through the following technical scheme: a coarse frequency measurement module directly performs fast Fourier transform, incoherent integration, spectrum smoothing and frequency coarse calculation on a received signal to obtain a carrier Doppler frequency shift coarse value; in a fine frequency measurement state, the Doppler pre-compensation moduleperforms Doppler pre-compensation on the received signal by adopting the carrier Doppler frequency shift rough value; the change rate pre-compensation module performs change rate pre-compensation on the sampling data according to the carrier Doppler change rate subdivision value; the multiple frequency measurement processing branches process data output by the grouping average module in parallel,the frequency fine calculation module estimates the overturning position of a modulation symbol in a received signal, the carrier Doppler shift and the carrier Doppler change rate of the received signal at the output moment are obtained through correction, and accurate frequency measurement of the high-dynamic weak MPSK signal is completed.

Description

technical field [0001] The invention belongs to the field of wireless communication, and relates to an accurate frequency measurement method for a highly dynamic weak multi-ary phase shift keying (Multiple Phase Shift Keying, MPSK) signal. [0002] technical background [0003] Multiple phase shift keying (Multiple Phase Shift Keying, MPSK) signal is a kind of linear digital modulation signal, which is a digital modulation method in which the keyed carrier phase is changed according to the baseband pulse. The more common one is binary phase shift Keying (2Phase Shift Keying, 2PSK) signal, that is, binary phase shift keying (Binary Phase Shift Keying, BPSK) signal, quaternary phase shift keying (4Phase Shift Keying, 4PSK) signal, that is, quadrature phase shift keying (Quadrature Phase Shift Keying, QPSK) signal, octal phase shift keying (8Phase Shift Keying, 8PSK) signal, etc. Compared with similar digital modulation signals, multi-ary phase shift keying (MPSK) signal can eff...

AI Technical Summary

Problems solved by technology

[0007] The present invention aims at the technical defects of low real-time frequency measurement, poor measurement accuracy, and inability to adapt to complex scenarios such as high dynamics and weak signals in the traditional frequency measurement method, and provides a method with good real-time performance, small measurement error, high estimation accuracy, and Accurate frequency measurement method for MPSK signals suitable for complex scenarios such as high dynamics and weak signals, providing high-precision measurement values ​​of carrier Doppler frequency shift and carrier Doppler change rate for subsequent signal processing

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