CAJ | 학술논문

为精确测量两个同频率信号的相位差，设计一种基于DSP的相位差测量系统。该系统采用DSP2812作为测量的主控芯片，其内部集成有捕获单元和A／D模块；运用信道交换技术和降频技术，消除通道带来的附加相移，并将高频信号转化为低频信号以便于测量。测试结果表明，两路输入信号相同时，输入信号频率过大或是过小，测量频率和相位的精度均会明显降低，幅值精度变化不大；两路输入信号峰值、频率相同，相位可变时，信号频率增加或信号幅值过小，系统的测量精度均会有所下降。该相位差测量系统能够实现对两路同频信号的幅值、频率和相位差的精确测量，且可以进一步扩展以实现对多路信号相位差的测量。
위정학측량량개동빈솔신호적상위차，설계일충기우DSP적상위차측량계통。해계통채용DSP2812작위측량적주공심편，기내부집성유포획단원화A／D모괴；운용신도교환기술화강빈기술，소제통도대래적부가상이，병장고빈신호전화위저빈신호이편우측량。측시결과표명，량로수입신호상동시，수입신호빈솔과대혹시과소，측량빈솔화상위적정도균회명현강저，폭치정도변화불대；량로수입신호봉치、빈솔상동，상위가변시，신호빈솔증가혹신호폭치과소，계통적측량정도균회유소하강。해상위차측량계통능구실현대량로동빈신호적폭치、빈솔화상위차적정학측량，차가이진일보확전이실현대다로신호상위차적측량。
For accurate measurement of the phase difference of the two same-frequency signals, a kind of phase difference measurement system based on DSP is designed. As the main control chip in the system, DSP2812 integrates capture unit and A/D module; Channel exchange technology and frequency reduction technology are used to eliminate additional phase shift by channel, and convert high frequency signals to low frequency signal before being measured. The test results show that the two input signals are the same, if the input signal frequency is too large or too small, the accuracy of measuring frequency and phase will be significantly reduced, little change in amplitude accuracy; two peak input signal, the same frequency, the phase can be changed, the increase in signal frequency or signal amplitude is too small, the system ac- curacy will decline. Experimental results show that the phase difference measurement system can well measure amplitude frequency and phase difference of two input signals with the same frequency. The system can also be further extended to realize to phase difference measurement of multi-channel signals.