Fiber optic subcarrier transmission system using coherence multiplexing techniques for broad-band distribution networks is proposed. This system makes it possible to improve the laser linewidth requirement and also to eliminate the effect of intermodulation distortion (IMD) which is serious problem in subcarrier multiplexed (SCM) system. In the proposed system, the frequency difference, /o, between the reference light and the signal light makes it possible to generate the broadband FM signal after photodetecting. Thus, an increase in the modulation index provides a corresponding increase in receiver sensitivity. We analyze the fundamental performance of the proposed system and derive the signal-to-noise ratio (SNR) at the output of FM demodulator by taking the threshold effect and spike noise into account. The proposed system can achieve the total capacity in excess of 10GHz, and thus it is attractive for multichannel broad-band distribution networks.
|ジャーナル||IEICE Transactions on Communications|
|出版物ステータス||Published - 1997 1 1|
ASJC Scopus subject areas
- Computer Networks and Communications
- Electrical and Electronic Engineering