Abstract

Multichannel distribution systems, based on optical WDM or FDM technology, are attractive for achieving large capacity, large subscriber networks. The target of these systems could be a more than 100-channel distribution to several tens of thousands of subscribers. Coherent technology is most attractive for achieving such large capacity distribution networks (see Fig. 1) because of its high receiver sensitivity and high resolution filtering characteristics with low crosstalk. In a coherent distribution system, the channel number is now limited by a receiver tunability of several hundred gigahertz.¹ To achieve more than 100 channels by overcoming this problem, highly dense packing with a cross polarized channel arrangement² or the use of multilocal oscillator receivers is extremely attractive.

© 1990 Optical Society of America