董宇飞,李开成,宋朝霞,贺才郡,范伟欣.基于改进CORDIC算法的快速幅频可调DDS技术[J].电测与仪表,2024,61(12):63-70. DONG Yufei,LI Kaicheng,SONG Zhaoxia,HE Caijun,FAN Weixin.A high speed amplitude and frequency adjustable DDS technology based on improved CORDIC algorithm[J].Electrical Measurement & Instrumentation,2024,61(12):63-70.
基于改进CORDIC算法的快速幅频可调DDS技术
A high speed amplitude and frequency adjustable DDS technology based on improved CORDIC algorithm
Aiming at the shortcomings that direct digital synthesizer circuit occupies more ROM resources and CORDIC algorithm occupies more logic resources and is hard to adjust the amplitude quickly, an improved CORDIC algorithm is proposed, which can quickly adjust the amplitude and frequency of DDS. The CORDIC module replaces the phase amplitude conversion module based on ROM look-up table in DDS, so as to greatly save the occupation of ROM resources. The CORDIC algorithm is improved by scaling-free technology, so that the amplitude can be adjusted quickly. Combined with iteration-merging technology, a phase amplitude conversion module based on improved CORDIC algorithm is proposed. The module eliminates the rotation direction judgment unit and cyclic iteration in the CORDIC algorithm, which greatly reduces the occupation of logic resources in circuit. The algorithm is implemented on FPGA platform, and the analog signal is output by DAC module for measurement. The experimental results show that the sinusoidal amplitude and frequency output by the algorithm have high accuracy and good amplitude modulation ability. It is suitable for various signal processing applications.
