Segmented matched filter with differentially coherent combined for PN code fast acquisition
Weigang Zhao, Yanhong Kou, Zhang Qishan · 2009
In high dynamic environment, the PN code acquisition is one of the most challenging step in the process of DS/SS systems Synchronization. Segmented matched filter (SMF) provides rapid acquisition with large frequency offset. A new scheme that differentially combine inner-symbolic sub-SMF correlation outputs and coherently accumulate over a number of consecutive symbols is proposed, and the maximum selection method is used to find the optimal aligned codephase. The theoretical derivation of probability density function of the detection variables in the proposed detector is done. Numerical simulation results with high dynamic GPS receiver show that the detection performance is tolerable to a large amount of initial frequency offset and data modulation of the DS-SS signal.