一种扩频接收机的设计分析

基于直接序列(DSSS)扩频通信原理,阐述了直接序列扩频接收机的组成和工作原理,对解扩解调部分进行了详细设计,给出了关键模块的原理和实现方法;尤其对扩频信号的自动增益控制、伪码捕获、伪码跟踪、载波跟踪以及定时同步等电路进行了细致论述,并说明了注意事项;最后,给出了硬件实现方式和测试数据。设计采用低成本的现场可编程门阵列(FPGA)和数字信号处理器(DSP)实现,具有灵活性强、速度快等特点,而且通过工程应用证明了设计是正确可行的。

Design and Analysis on a Spread- spectrum Receiver

Based on DSSS （Direct Sequence-Spread Spectrum） principle, the composition and working principles of DSSS receiver is studied. The parts of de-spread spectrum and de-modulation are discussed in details, and the principles and method of the key modules are put forward. Especially the automatic gain control, PN code acquisition, PN code tracking, carrier tracking, timing synchronization circuits and so on are discussed in detail and some adviees are presented. Finally, the method of hardware implementation and test data are given. The design is realized based on low-cost FPGA and DSP, with the characters of high agility, high speed and so on. The design is practiced and correct.