Performance optimization of RZ-DQPSK modulation scheme for dispersion compensated optical link

This paper presents a simulative analysis for performance optimization of RZ-DQPSK modulation scheme for dispersion compensated Amplified Spontaneous Emission (ASE)-noise-limited optical link at 10 Gbps. The link performance analysis has been carried out for different duty cycles of RZ-DQPSK to achieve an optimized performance of the system at 80% duty cycle. The analysis has also been extended to three different types of commonly used optical fiber: SSMF, TW-RS and LEAF to report the similar qualitative behavior for the optimized duty cycle of the modulation scheme considered. The investigation reported in the paper helps in selecting the type of the fiber and best suitable duty cycle for long distance communication.