Self-adapting signal detecting method for eliminating frequency offset interference

Abstract

The invention discloses a self-adapting signal detecting method for eliminating frequency offset interference, which comprises the following steps of: S1 adding a pseudo-random code into a frame head of a data frame as a lead code by a sending end, and sending the sampled data frame; S2 multiplying the received data frame by delay thereof in a conjugating way by a receiving end after receiving the data frame to obtain the received signal which eliminates the frequency offset; S3 dividing the received signal into two same signals, respectively computing a statistical decision quantity and setting a self-adapting threshold; and S4 comparing the magnitude of the statistical decision quantity with the magnitude of the self-adapting threshold, and outputting an identification signal which indicates that an effective signal is detected if the statistical decision quantity is larger than the self-adapting threshold. The method eliminates the frequency offset generated during signal transmission by means of conjugate multiplication, reduces the computation quantity, improves the computation speed, improves the detecting precision of the signal, and is stable in performance, simple in structure, and easy in realization.

Description

technical field [0001] The invention relates to a signal detection method in the field of burst communication, in particular to an adaptive signal detection method for eliminating frequency offset interference. Background technique [0002] In the burst mode of wireless communication, the receiver must have reliable signal detection to ensure accurate recovery of the transmitted data. However, in the actual wireless communication environment, the carrier frequency offset caused by the error of the crystal oscillator of the transceiver or the Doppler frequency shift generated in the high-speed mobile environment will interfere with the correlation performance of the pseudo-random sequence and affect the signal detection. The larger the frequency offset, the smaller the correlation peak. In the case of a large frequency offset, the autocorrelation peak of the pseudo-random sequence will be submerged, and no obvious peak will appear, which will affect the detection performance...

AI Technical Summary

Problems solved by technology

Among them, the FFT transform method based on partial matched filtering and the frequency compensation method are both based on FFT transform. The inherent limitations of FFT transform make the above two methods have the problems of incomplete frequency offset compensation and large amount of calculation.

However, the segmented matched filter method fights against frequency offset at the cost of loss of signal-to-noise ratio, and its peak signal-to-noise ratio loss increases with the increase of frequency offset tolerance range.

Therefore, the performance of signal detection methods that eliminate frequency offset interference needs to be improved urgently

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