Estimation and identification techniques for DS/SS signals

Conventional intercept receivers based on second order signal processing are generally ineffective in detecting direct-sequence spread spectrum (DS/SS) signals if the spreading sequences are unavailable. An investigation into using correlation-based processing is reported showing that the cyclostationary property of DS/SS provides detection capability. Finally we describe with results an emerging technique based on higher-order statistics where bispectral analysis is used for detection together with triple correlation for identification, leading to an estimation of the DS/SS modulated chip code sequence(s) operating in noisy channels even if only a fragment of the code is available