Using coherent lightwave technology in an optical frequency division multiplexing (FDM) system has been widely investigated recently to achieve large- capacity optical networks.1 This paper studies channel capacity in a coherent FDM distributing service system (Fig. 1), considering the local oscillator tuning range (ch. 1 to ch.n) and the desired channel spacing (ch. 1 to ch.2). The optical FSK heterodyne dual-filter detection system is examined, because the FSK system is considered to be most practical from laser linewidth and modulation considerations.
© 1988 Optical Society of AmericaPDF Article