Robust Detection of DSSS Signals in Non-Cooperative Context

Abstract

At present, the blind detection of DSSS (direct sequence spread spectrum) signals is mainly based on the cyclostationarity of the signals and uses the statistics analysis of the second or higher order eigenvalues as a cut-in sticking point for resolving the problem, it is quite easily influenced by the low signal to noise ratio and restricted by the implementation of the algorithm. In order to resolve the problem of the blind detection, the paper proposes a blind spread spectrum pseudo random sequence detection method: multi-chip allied correlation detection, and a blind chip synchronization method: multi-codeword correlation smoothing match. The proposals of the paper resolve the bottleneck problems in the blind detection of DSSS signals: the blind spread spectrum pseudo random sequence estimation and the chip synchronization search in the context of low signal to noise ratio. The proposed methods not only avoid the need of the second or higher order processing of many blind detection methods, reduce the complexity of the blind detection of DSSS signals greatly, but also overcome the shortcoming of many blind detection methods while dealing with the spread spectrum transmission far below the noise level. The paper may be a foundation for achieving the detection of the DSSS signals in non-cooperative context.