高性能DDS正弦信号源设计与实现  

Design and implementation for sinusoidal signal source of high performance DDS

作　　者：李颖[1] 邱育杰 

机构地区：[1]电子科技大学电子工程学院,四川成都611731

出　　处：《现代电子技术》2015年第23期37-40,共4页Modern Electronics Technique

摘　　要：为了节约硬件资源,同时获得高信噪比的正弦信号,采用CORDIC算法和Δ-Σ调制器产生DDS正弦信号,由CORDIC产生多比特的正弦信号数据,再利用Δ-Σ调制技术把多比特的正弦信号转换为1 b的数据流,最后经过低通滤波器滤除混叠的频谱得到正弦信号,这种技术优势在于精度高、成本低、硬件结构简单。通过仿真及硬件测试,所设计的DDS无杂散动态范围可达到56.1 d Bc,信噪比在100 d B以上,幅度衰减误差小于0.5%,表明该方法具有分辨率高、速度快和频谱杂散小等优点。To save hardware resources and obtain the sinusoidal signal with high signal-to-noise ratio, the CORDIC （coordi- nation rotation digital computer） algorithm and △-∑ modulator are adopted to generate DDS sinusoidal signal. The multi-bit data of the sinusoidal signal is generated by CORDIC algorithm, then the sinusoidal signal is converted into data flow of 1 bit by means of △-∑ modulation technology, and the sinusoidal signal is obtained by filtering the aliasing frequency spectrum through low-pass filter. The advantages of this technology are high accuracy, low cost and simple hardware structure. The simulation and hardware test results show that the designed DDS spurious-free dynamic range （SFDR） can reach up to 56.1 dBc, the signal-to- noise ratio is better than 100 dB, and the amplitude attenuation error is less than 0.5%, which indicate that the method has the advantages of high frequency resolution, fast speed and less stray frequency spectrum.

关 键 词：DDS CORDIC算法 △-∑调制器 正弦信号源 

分 类 号：TN911.7[电子电信—通信与信息系统] TP391.4[电子电信—信息与通信工程]