Non-cooperative detection of weak spread-spectrum signals in additive white Gaussian noise

A semi-blind method based on principal component analysis and sequence synchronisation is proposed to detect direct sequence spread-spectrum signals in a non-cooperative setting under low signal-to-noise ratio conditions. The intercepted signal is segmented to form a detection matrix from which a feature is extracted through cyclic shifting. Signal detection is then performed using a test statistic based on this feature. The carrier frequency and sequence duration of the signal to be detected are assumed known. Theoretical analysis and a computer simulation study show that the performance of the new detection method is superior to classic energy detection in an additive white Gaussian noise channel.