摘要
Abstract
According to ASKdigital modulation mode,a new type of modulating and demodulating circuit was designed. The method of anolog AM modulation is adopted in modulating circuit. Anolog multiplier AD734 is used to realize that the carrier is multiplied by the modulated binary digital signal so that the modulation is completed. The method of envelope detection is ad-opted in demodulating circuit. The operational amplifier LMH6658MA is used to realize that the sine signal amplification and am-plitude-limit is converted into square wave signal. At the same time,the signal is rectified with the rectifying circuit in compara-tor. And then,the carrier is filtered by a low-pass filter. At last,the signal is reshaped by differential circuit and comparator LM139 to get the demodulated binary digital signal,so that the demodulation is completed. The designed modulating and demod-ulating circuits were simduated and verified by Proteus. The result shows that the circuits have characteristics of simplicity, large dynamic range in signal amplitude and frequency.关键词
ASK/调制电路/解调电路/Proteus仿真Key words
ASK/modulating circuit/demodulating circuit/Proteus simulation分类
信息技术与安全科学
