Direct sequence spread spectrum signal interception detection method

Abstract

The invention discloses a direct sequence spread spectrum signal interception detection method. The method comprises the steps of 1, obtaining a data sequence x (n); 2, obtaining a self-correlation sequence r (m); 3, smoothing the r (m); 4, setting a search step j; 5, estimating an accumulation amount C (j); 6, searching the maximum value C (jmax) of the accumulation amount C (j); and 7, carrying out detection judgment and pseudo code cycle estimation. According to the detection method provided by the invention, the direct sequence spread spectrum signal interception detection can be realized only by use of the one-time self-correlation estimation result; through accumulation of correlation peaks of the self-correlation sequence and step variable search, the processing gain is improved; the influence of information codes is reduced; the detection performance is improved; the process is simple; and the prior information is unnecessary.

Description

technical field [0001] The invention belongs to the technical field of communication and signal processing, and relates to a method for interception and detection of direct spread signals, which is used for interception and detection of direct spread signals under non-cooperative conditions. Background technique [0002] Direct sequence spread spectrum (hereinafter referred to as direct spread) technology has been widely used in the field of underwater acoustic communication and detection. Because its energy is dispersed in a wide frequency band and the energy per unit frequency is low, the interception and detection method under non-cooperative conditions has become a communication method. Research hotspots and difficulties in countering underwater acoustics. Existing detection methods for DS signal interception mainly include: energy detection method, square law method, correlation accumulation method, and period spectrum-based method. The traditional energy detection met...

AI Technical Summary

Problems solved by technology

The correlation accumulation method makes use of the autocorrelation characteristics of the direct spread signal pseudo code, but in order to obtain high gain, multi-segment data autocorrelation estimation is required for cumulative averaging. In the underwater acoustic field, the propagation speed is slow, and multi-segment data acquisition takes a long time, and the actual When the signal is short, multi-segment accumulation introduces more noise, and the gain decreases instead.

The periodic spectrum method has better performance, but it is difficult to implement

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