Detection technique for code acquisition in DS-SS systems employing PN matched filters

This paper presents a threshold decision technique for direct sequence code acquistion employing Pseudo-Noise(PN) matched filter. The probabilities of detection and false alarm are derived as a measure of the system performance in both nonfading and nonselective Rician fading channels. For received PN codes with different SNR, the proposed acquisition scheme is able to detect a desired threshold in the search mode so that this value is utilized as a threshold for the verification mode. Thus, there is no need to determine a threshold by applying the Neyman-Person ciriteron. It is shown that this scheme achieves lower probability of false alarm than the acquisition scheme based on the Neyman-Person criterion, giving comparable performance in terms of the probability of detection.