Adaptive double-dwell PN code acquisition in direct-sequence spread-spectrum systems

An adaptive double-dwell acquisition system of pseudo-noise (PN) sequences is presented for direct-sequence spread-spectrum (DS-SS) systems. Since existing acquisition systems have a fixed threshold value, they are unable to adapt to various mobile communications environments. Accordingly, this results in a high false alarm rate or low detection probability. Therefore, an adaptively varying threshold scheme is proposed through the use of a constant false alarm rate (CFAR) algorithm. By deriving formulas for the detection probability and false alarm rate of the proposed adaptive system, its performance was analyzed and compared to an existing one. The results showed that the proposed adaptive double-dwell acquisition system. Provides a better performance than conventional systems