基于查找表和CORDIC算法的混合型NCO设计

摘要

针对常用的在FPGA上实现NCO的查找表法和CORDIC算法存在的不足，提出一种基于查找表和CORDIC算法相结合的 NCO 实现方法。对查找表法、CORDIC 算法以及查找表和 CORDIC 算法相结合方法的实现原理进行设计，并分别对3种不同实现方式进行仿真和对比分析。结果表明：用查找法和CORDIC算法相结合的方法实现的NCO能很好地平衡FPGA上存储器资源和逻辑资源的消耗，并在产生信号的精度、速度、纯度方面也有很好的兼顾。%Aiming at the shortcoming of NCO look-up table method and CORDIC method in FPGA. Put forwards a NCO realization method which combined look-up table method with CORDIC method. Design realization principle of look-up table method, CORDIC method and method which combined look-up table method with CORDIC method. Then carry out simulation and comparison analysis of three methods. The results show that the NCO that is achieved by the combination of the look-up table and the algorithm of CORDIC can well balance the consumption of the memory resources and the logical resources and it can give consideration to the accuracy, speed, and purity of the signals it produces.