When processing digital base-band, the signalof pilot-frequency was taken out from normal carrier channel and it would be used for transmitting pseudo pilot-frequency.
在数字基带处理时，从正常载频信道中提取出导频信号，用于伪导频的发射。
2
Finding out the major concentrated frequency bandof tool-wear information can enhance SNR (Signal Noise Ratio) and improve tool-wear degree recognition result.
找出刀具磨损信息在可听阈内的主要集中频段能提高切削声信号的信噪比，改善识别结果。
3
The outband spurious spectrum is limited by raised cosine filter in transmitter, and the shadow effect can be removed by combining the signal power of two branches in receiver.