摘要
雷达中频信号模拟器要求中频回波信号具有非常高的精度。为此采用直接数字频率合成技术(DDS),以DDS芯片AD9850为中频信号的合成与输出芯片,以单片机AT89C51为频率控制字的输出芯片,结合其他外围元件设计了一套中频信号源,并以AD9850的频率控制字为基础,针对AD9850的控制时序,进行了单片机内的软件设计。实践证明,该信号源输出的中频信号稳定性好、精度高,完全满足设计指标要求。
Simulator for intermediate frequency（IF）in radar requires IF echo signal with high precision. Aiming at generating IF echo signal, which matches the requirement, An oscillator system based on directly digital synthesizing（DDS） technology is designed. The system is mainly consisted of a DDS chip AD9850 for synthesizing and outputting IF signal. Besides, a single-chip micro computer AT89C51 is utilized for realizing frequency control words of AD9850. The software is also designed for controlling AD9850 based on frequency control words. Experiments prove that the system turns out the advantages of high precision and high operating reliability for outputting IF signal, which matches the design requirement well.
出处
《国外电子测量技术》
2009年第4期43-45,共3页
Foreign Electronic Measurement Technology
