Method for improving incoherent detection performance of MSK (minimum shift keying) signals

Abstract

The invention provides a method for improving the incoherent detection performance of MSK (minimum shift keying) signals, and aims at providing the method solving the problem of MSK signal application limitation caused by poorer incoherent detection performance and realization difficulty of coherent detection of the MSK signals. The method provided by the invention is realized through the following technical scheme that in an MSK data transmission receiving machine, a signal capture module stores baseband signals after the down-conversion into a memory, then, a high-speed clock is used for reading out the stored signals from the memory, next, the read signals are subjected to frequency offset compensation and bit synchronization searching according to the pre-divided frequency grooves, and the searching results are sent to a signal tracking module; the signal tracking module realizes the frequency and bit synchronization tracking through a frame head waveform matching correlator according to the capture results sent from the signal capture module; and a correlation judging module carries out correlation calculation on the signals sent by the signal tracking module with the local waveforms, selects the maximum correlation value from the correlation results and adopts the bit of the maximum correlation value corresponding to the middlemost part of the bit flow as the final judgment results to be output.

Description

technical field [0001] The invention relates to a method for improving non-coherent detection performance of minimum frequency shift keying MSK signals, and is suitable for detection of continuous or burst MSK signals. Background technique [0002] The MSK signal is a continuous phase modulation signal (CPM) with a modulation index of 0.5, which has the advantages of concentrated energy, constant envelope, and high spectrum utilization. In addition to the above advantages, the burst mode MSK signal also has short duration , Concealment is good, and it is widely used in wireless communication fields such as data links. There are two methods of MSK signal detection, coherent detection and non-coherent detection. [0003] The coherent detection of the MSK signal has the characteristics of good detection performance, but the precondition for the application of the coherent detection is that the coherent carrier can be extracted, which is very difficult for the MSK signal. It ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problems in the prior art that MSK signal coherent detection is not easy to realize, non-coherent detection performance is poor, and the application of MSK signal is limited due to high demodulation threshold, and to provide a method of using known frame header information to assist MSK signal. Acquisition and tracking of Doppler frequency offset, bit synchronization and frame synchronization, using signal waveform matching correlation to complete signal judgment

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