在电信网络中传送数据时经常出现码间干扰,并引起误码。产生码间干扰的原因是调制解调器的传输信号通过网络时,信号的时间延迟随频率变化。时间延迟不太影响语音信号,但是影响数据信号,如:调制解调器发出的信号。为了保证用户希望的无误码传输,调制解调器设计者要补偿他们设计的电路,以保证全部信号有相同的延迟。 调制解调器设计者需要测量延迟变化量,以验证补偿电路的设计是否正确。测量包络延迟的传统方法是单音扫描法,此法很费时间,而且繁琐。本 Inter-symbol interference often occurs when transmitting data in telecommunications networks and can cause bit errors. The reason for inter-symbol interference is that the signal’s time delay varies with frequency as the modem’s transmission signal travels through the network. The time delay does not affect the voice signal much, but it affects the data signal such as the signal sent by the modem. In order to ensure that users want the error-free transmission, modem designers to compensate for the circuit they designed to ensure that all signals have the same delay. Modem designers need to measure the amount of delay variation to verify that the compensation circuit is designed correctly. The traditional method of measuring the envelope delay is the mono-tone scanning method, which is time-consuming and cumbersome. this