OPTICAL FREQUENCY MULTIPLEXER AND OPTICAL FREQUENCY MULTIPLEX TRANSMITTER

摘要

PURPOSE:To attain optical frequency multiplexing with a narrow channel interval by providing an optical filter having a pass band passing a required minimum spectrum for demodulation of a signal with respect to each signal constituting an optical frequency multiplex signal into a transmitter. CONSTITUTION:Plural electric signals (total channel number N) enter an optical frequency multiplex signal transmitter 1 and they modulate directly transmission light sources...4(n-1), 4n, 4(n+1)... respectively (n is a channel number satisfying 1n=N). Moreover, an optical coupler 5 multiplexes and outputs a broad band frequency shift keying(FSK) optical signal outputted from each transmission light source 4. Then an optical filter 6 receives a multiplex signal and has a pass band nearly coincident with the frequency of each signal. Thus, the optical frequency multiplexer 1 able to apply optical frequency multiplex to the signal with a narrow channel interval and an optical frequency multiplex transmitter able to send the optical frequency multiplex signal are realized with simple constitution.