基于DSP和FPGA的嵌入式数字直接序列扩频系统的研制

介绍了一种基于Xilinx公司的FGA(Spartan2 XC2S200)和TI公司的DSP TMS320VC5410设计的直接序列扩频收发机，其下变频后的部分，如PN码的捕获、跟踪、基带解调(去掉剩余频差)等全部采用FPGA数字实现。对PN码的捕获，采取了一种门限自适应控制的双积分滑动相关捕获方法，既大大节省了FPGA的硬件设计资源，又能使PN码的平均捕获时间足够小。经实验测试，该系统各参数完全达到设计要求。

Design of an Embedded Digital DSSS System Based on DSP and FPGA

A digital DSSS system is introduced ,which is designed with FPGA Spartan2 XC2S200 of Xilinx company and DSP TMS320VC5410 of TI company. The designs of acquisition,tracking and baseband demodulation after downconvertion to baseband are based on FPGA. For acquisition,the authors present a method of double dwells serial-search DS acquisition with adaptive threshold. It not only saves much hardware resource, but also can have a short period of acquisition. This system has already passed all tests.