Effect of partially coherent laser source on the performance of fiber-coupling DPSK receiver for optical communication

• The performance of DPSK receiver with partially coherent laser is studied.
• The DPSK receiver performance model of partially coherent laser is proposed.
• The statistical distribution of the fiber-coupling efficiency is given.
• The system fade margin, the average BER and the power penalty are obtained.
• The work can improve the redundancy design of fiber-coupling DPSK receiver.

In practice, due to the reasons related to the laser device and the inevitable error of the processing technique, a laser source emitted from a communication terminal is represented by partially coherent laser source. The fiber-coupling efficiency and the incident optical power at the receiver aperture are affected by the source coherent parameter ζ through atmospheric turbulence. In this paper, the statistical distribution of both the fiber-coupling efficiency and the incident optical power are given, based on which the effect of the source coherent parameter ζ on the performance of fiber-coupling differential phase-shift keying (DPSK) receiver is systematically analyzed. The system fade margin, the average bit error rate (BER) and the power penalty are obtained in the presence of the degradation of the source coherent degree. The results manifest that the performance of fiber-coupling DPSK receiver system degrades drastically with increasing source coherent parameter ζ. The hope of this work is to improve the redundancy design of fiber-coupling DPSK receiver system.