LS码及其FPGA的实现

Design and Implementation of LS Code Based on FPGA

LS码是一种基于互补结构的具有零相关性质的扩频地址码,有着优良的抗干扰性能,越来越受到人们的关注。LS码在FPGA中的实现具有易移植性、可重复性以及设计灵活的特点。针对LS码的构造和性质,详细介绍了树形结构生成算法以及扩频和解扩过程,对扩频的并行输出模块、串行输出模块以及并行解扩模块进行了时序仿真和下载测试,在设计输入时采用了查找表和混合实现方式,提高了芯片的处理效率,结果表明,该算法在系统上电启动运行后输出正确。

LS code based on the complementary structure is used to Spread Spectrum（SS） with the characteristic of Zero Correlation Window （ZCW）. The ZCW can better resist the interference in wireless communication systems, so more and more people exhibit a great interesting in it. On the other hand,the implementation of LS code based on FPGA has the characteristic of easy portability, the reused possibility and flexible design. Considering the construction and property, the arithmetic of tree structure,SS and De- Spread spectrum（DSS） are detailed introduced. Furthermore, the timing simulation and the test result after FPGA configured are given. The method of look - up table and mix- design are employed in design entry which increase the chip efficiency. The result shows the output is exactly correct when the hardware platform powered on.