公开(公告)号：EP0208270A3

公开(公告)日：1988-11-23

申请号：EP86109108

申请日：1986-07-03

申请人： NEC CORPORATION

发明人： Takahashi, Kunihiko C/O NEC CORPORATION

IPC分类号： H04L01/22

CPC分类号： H04L27/0008 ,  H04L1/22

摘要： A multichannel microwave relay station has first and second channels for respectively transmitting signals of different types of modulation, such as QAM and FM modulated signals. These different types of signals rely on a common standby transmission channel that is selectively capable of transmitting the different types of signals. The type of signal currently carried by the standby channel is automatically Identified by a detector circuit (6), such as one that can auto matically distinguish differences in the frequency spectrums of the different types of signals. A selecting circuit (3) responds to the output of the detector circuit (6) by selecting between first and second transmitting means (5) in the common channel, thereby dedicating it to the identified type of signal.