Detection performance of LPI waveforms of chaotic spread-spectrum systems with antenna arrays

Low probability of intercept (LPI) performance of a direct-sequence (DS) spread-spectrum (SS) system with chaotic spreading sequences has recently been investigated considering energy detectors, synchronous/asynchronous and coherent/noncoherent intercept receivers with a binary detection approach. In this paper, a simple detection scheme using two antenna elements is proposed to detect the presence of chaotic signals. The detection probabilities under the proposed method are derived and expressed in terms of the antenna spacing. Comparisons between systems using binary correlation methods and the proposed methods are given in terms of the LPI performance. The improvement of the detection performance under the proposed detection method is observed.