An Accurate Frequency Measurement Method for High Dynamic Weak MPSK Signals

Abstract

The invention discloses an accurate frequency measurement method for high dynamic and weak MPSK signals, aiming to provide an accurate frequency measurement method that can adapt to complex scenes of high dynamic and weak signals. The invention is realized through the following technical solutions: coarse frequency measurement The module directly performs fast Fourier transform, incoherent integration, spectrum smoothing, and frequency rough calculation on the received signal to obtain a rough value of carrier Doppler frequency shift; in the fine frequency measurement state, the Doppler pre-compensation module uses the above-mentioned carrier Doppler Doppler pre-compensation is performed on the received signal by the rough value of the Le frequency shift. The rate-of-change pre-compensation module performs pre-compensation on the rate of change of the sampled data according to the subdivision value of the carrier Doppler rate of change. Multiple frequency measurement processing branches process the group average in parallel. For the data output by the module, the frequency fine calculation module estimates the inversion position of the modulation symbol in the received signal, corrects and obtains the carrier Doppler frequency shift and carrier Doppler change rate of the received signal at the output time, and completes the accurate detection of high dynamic weak MPSK signals Frequency measurement.

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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