Pseudo-noise Code Acquisition Method Using Iterative Message Passing Techniques Based on Hybrid Iteration Strategy

In this paper, a pseudo-noise code acquisition method using iterative message passing techniques based on a hybrid iteration strategy is proposed. This method combines an internal iteration strategy with an external iteration. The proposed method not only avoids the confusion of the correct information flow caused by the switch of the graphical model in external iteration under a low signal-to-noise ratio but also solves the limitation problem of the detection performance after a few internal iterations caused by short cycles. In addition, this study proposes rearranging the subsets of parity-check equations after each external iteration to avoid the convergence of the iteration process to a local optimum to a certain extent. The simulation results demonstrate that the proposed algorithm can achieve better detection performance with fewer iterations than those of the existing algorithms.