Coherent High-Speed Signal Transmission in Passive Optical Networks

Abstract

A comparative study of digital M-ary Quadrature Amplitude Modulation (16-QAM) and QPSK modulationformats for high-speed transmission is presented. Based on VPI optical simulation software. This paper builds a high-bit rate dual polarization (DP) QPSK and16-QAM modulation formats coherent optical transmission system for Passive Optical Networks (PON). Higher-order modulation formats could be used to provide huge data capacity, extended coverage, and long-reach connections. Channel impairments are mitigated by using digital signal processing (DSP) for dispersion compensation, carrier frequency recovery, and carrier phase estimation. The performance of our system is analysed on Bit Error Rate (BER=1e-9), the threshold for a communication system. For a 32-Splitter PON configuration operating with 16-QAM modulation format, a data rate of 80 Gb/s per ONU is achieved after 24km using standard single mode fibre (SSMF). The results indicate that the proposed schemes are a promising solution for coherent high-speed transmission in PONs.