Multichannel Coherent Subcarrier Multiplexed Lightwave Systems Employing Continuous Phase Modulation Schemes

Abstract

Multichannel coherent subcarrier multiplexed lightwave systems are considered in this paper. The continuous phase modulation schemes are employed at the microwave level over multioctave subcarrier frequency bands, and analyses are presented for M-ary continuous phase frequency shift keying and multi-h codes. A complete description of the system performance in terms of the carrier-to-noise ratio, intermodulation distortion and receiver sensitivity is given for each of the M-ary cases (M = 2, 4, 8 and 16). It is demonstrated that significant improvement in system performance can be achieved by increasing the signal alphabet size M from 2 to 4.