高输出功率正弦信号发生器

基于直接数字频率合成DDFS（Direct Digital Frequency Synthesize）技术，依据调制信号相关原理，设计以DDS集成电路AD9851为核心的正弦信号发生器，可精确输出幅度调节范围为50mVPP-20VPP，频率调节范围100Hz-30MHz的正弦波。还可输出调幅波、调频波、PSK、ASK信号。该设计在宽频带内能获得大幅度的低失真波形。采用多种抗干扰措施以减少噪声并抑制高频自激，通过软件补偿提高频带内输出幅度的平坦度。该系统输出波形谐波失真度小，无杂散动态范围（SFDR）39．8dBc，功能稳定，操作简便。

Sine signal generator with high output power

Based on the technique of direct digital frequency synthesize （DDFS） and the theory of signal modulation,a sinusoidal generator with core chip AD9851 is designed,whose frequency range is 10014z-30MHz and amplitude range is 50 mVPP-20VPP The sinusoidal generator also outputs of FM, AM, PSK and ASK signals.The system design achieves wide amplitued,low distortion wave.Taking anti-interference measures ,and takes the advantage of software compensation, the system exports high accurate waveform,whose SFDR is up to 39.SdBc,and has the stable funtion and convenient operation.