基于DDS技术的无线测距信号源设计

Design of Wireless Ranging Signal Source Based on the DDS Technology

为了提高测距信号频率的稳定性,减小频率不稳引起的测距误差,将DDS(Direct Digital Synthesis,直接数字频率合成)技术应用到连续波相位式无线测距系统的信号源设计中。设计以DDS芯片AD9850为核心的测距信号源,给出具体的软、硬件实现方法。测试结果表明,采用DDS技术设计的测距信号源与基于PLL(Phase Lock Loop,锁相环)的信号源相比,具有频率稳定度高,频率切换速度快,相位噪声低等优点。

For the purpose of improving the stability of ranging signal and decreasing the ranging error in a consecutive wave phasic wireless ranging system .The DDS (Direct Digital Synthesis) technology was used in designing the signal source .The paper designes a signal source of wireless ranging system by using the DDS chip named AD9850 , and the implementation of hardware and firmware was given .The signal source had superiority in frequency stability , speed of switching frequency and phase noise when compared with the signal source based on PLL (Phase Lock Loop).