Research On Pseudo-random Codes Synchronization For PCSS Systems

Parallel Combinatory Spread Spectrum System(PCSS) is a kind of spread spectrum communications that has a highly band utilization, at the same time this system inherited advantages from traditional spread spectrum such as anti-interference, low probability of intercept, superior multiple access communication ability, etc. So this system has a broad application prospect and apply to the applications such as Burst spread spectrum communication, high information rate spread spectrum communication, etc.The information in PCSS is equiamplitude modulated by Pseudo-random Codes, in order to capture the PRCs we have to solve the problems of increased amount of calculation and the cross-correlation interferences between PRCs. Therefore, research in appropriate way to capture Combination PRCs is very necessary. In this paper, we comprehensive considered the principle and the parameter characteristics of PCSS to research the suitable way of PRCs capture. The main research content includes the following several aspects:(1) Based on the relevant algebra and characteristics of CPRC, combined with the formula derivation and simulation analysis in this paper, a suitable way that combination pseudo-code self synchronous capture mode, namely the combination of multiple series of PRCs and the local PRCs correlation respectively, according to the modulation of system parameter selection of the big related value added as the capture alternative peak. This method improves the system acquisition probability at the receiving end, enhance the anti-interference ability of the system.(2) Combining it is concluded that the combination of pseudo-code capture mode, will be applied to single PRCs acquisition synchronization head, sliding correlation, matched filtering and Fast Fourier (Fast Fourier Transformation, FFT) capture algorithm is applied to the combination of PRCs such as capture, capture puts forward several solutions. Simulation verify the capture probability of each method and application in the system bit error rate,through comparative analysis, it is concluded that FFT capturing algorithm can solve more complex computational complexity of the problems of pseudo-code modulation mode, and the scheme has good capture performance.(3) Analyzes the parallel combination of spread spectrum modulation parameters on the combined effect of pn code acquisition probability. Communication efficiency in parallel combination of spread spectrum systems, computational complexity and ber performance from several aspects, discussed the synchronization mode modulation parameters selection,the optional parameters is given.