Patent ID: 7209493

Claim:
A multiplex transmission system that multiplexes signals of the arbitrary number by time division and transmits a multiplexed signal to a transmission line interface having predetermined frame configuration, wherein: the multiplex transmission system comprises: a transmitter that converts a signal from each input channel to a frame of a predetermined internal interface, generates an internal signal by inserting a specific idle frame different from an idle frame inserted into a surplus band of a signal of another input channel into a surplus band of a signal of a predetermined input channel, multiplexes internal signals by time division, generates a multiplexed signal and transmits it to the transmission line interface; and a receiver that establishes synchronization of the transmission line interface, detects the multiplexed signal, detects the specific idle frame in the multiplexed signal, specifies a position multiplexed by time division of each internal signal based upon a position of the specific idle frame, demultiplexes each internal signal, removes the idle frame or the specific idle frame from each internal signal, restores the predetermined internal interface to the original interface and transmits to each output channel.