An Approach to Estimate The Pseudo-code Period and Chip Rate of Direct Sequence Spread Spectrum Signals Simultaneously

The first task in the fields of non-cooperative radio surveillance,communication management and control of direct sequence spread spectrum(DSSS) communication is to detect and estimate the DSSS signals and the related parameters,which includes pseudo-code period,chip rate,etc.Because the power spectrum density of DSSS signal is often too low to be covered by noises,so that the normal methods of signals detection and estimation could not be applied directly.Aiming at the problem of detection of DSSS signals,pseudo-code period and chip rate estimation,this paper synthesizes the correlation methods of DSSS signals processing,proposes the auto-correction method which can detect the DSSS signals and estimate the parameters of pseudo-code period and chip rate simultaneously.Theory analysis and experiment results show that the proposed methods can effectively detect and estimate the DSSS signals and their parameters under the low signal noise ratio environment.