基于DDS技术的高频信号源设计与实现

Design and Implementation of High Frequency Signal Source Based on DDS Technology

介绍了一种基于直接数字频率合成(DDS)技术的高频信号源的设计与实现。该系统以单片机STC89C54RD+和DDS芯片AD9851为核心,产生正弦波信号,通过AD835与THS6002实现幅度数控调整,最终实现了输出频率、幅度和占空比可调的正弦波和脉冲波信号。实测结果表明:该高频信号源输出频率为0～70 MHz;幅度为0～10 V(P-P);脉冲信号的占空比为5%～95%,且都实现了数控可调,具有信号的频率误差小、分辨率高和幅度稳定等优点。

The design and implementation of high frequency signal source based on the direct digital synthesis （DDS） technology are described. This system is designed by MCU STC89C54RD ＋ and DDS chip AD9851 which is as the core pro- duce sine signals. Finally, the output frequency, amplitude and duty cycle of sine wave and pulse wave which can be adjus- ted are achieved by AD835 and THS6002. The experiment results show that the output frequency of high frequency signal sources is 0 -70 MHz, the amplitude is 0 ~ 10 Vp_p, the pulse duty cycle is 5% -95%, and the high frequency signal sources realize numerical control with a less signal frequency error, higher resolution and more stable amplitude.