CORDIC算法在跟踪环中的应用与FPGA实现

主要介绍了坐标旋转数字计算（CORDIC）算法在跟踪环鉴别器中的应用,包括码跟踪环、锁频环和锁相环鉴别器,并进行了FPGA实现。在设计中,采用统一CORDIC算法优化方法减少硬件开销,用非流水方式在一个CORDIC运算基本单元中实现了码跟踪环、锁频环和锁相环三种鉴别器。同时对CORDIC运算的精度和位宽进行分析,在保证环路功能的情况下尽量减少硬件资源的使用。在Virtex5lx220上测试使用了该鉴别器的GPS跟踪环,取得了满意的跟踪效果。

Application of CORDIC Algorithm in Tracking Loop and FPGA Implemenntation

This paper describes the application of CORDIC algorithm in tracking loop discriminators,including the discriminator in code tracking loop,phase-lock loop and frequency-lock loop,and FPGA implementation.A unified CORDIC algorithm is adopted in the design,thus to reduce hardware overhead.The three tracking loop discriminators are implemented by using a non-pipelined basic unit of CORDIC caculation.Meanwhile,the precision and bit-width of CORDIC calculation unit is analyzed,thus to ensure the good performance of loop discriminators and minimize the hardware resources.Test of the proposed loop discriminators in a GPS tracking loop on Virtex5 lx220,indicates a satisfactory tracking performance.