Comparative investigation on 10G-class and 25G-class receivers for O-band DML-based 25/50 Gbps TDM-PON

Abstract

Abstract Reliable and cost-efficient transceivers are desired for next generation high-speed passive optical network (PON). In this paper, we experimentally demonstrate 25/50 Gbps transmissions based on an O-band directly modulated laser (DML), and the receiver-side solutions are investigated in detail to realize a low-cost high-speed PON system. Specifically, a comprehensive comparison of two commercially available receiver candidates is presented, which are the 10G-class receiver and the 25G-class receiver. Three typical transmission cases for next generation PON systems based on these two receivers are demonstrated, and the system bandwidth limitation induced signal distortions in corresponding cases are compensated by equalization-based digital signal processing (DSP). System performances and the DSP-induced implementation complexity of the two receivers are comprehensively analyzed and compared. Results indicate that, for the 25 Gb/s transmission, the 25G-class receiver without any DSP is more favorable than the 10G-class one with post-equalization, and a power budget of 25.4 dB is achieved without amplification for non-return-to-zero on-off keying (NRZ-OOK) signal. While for the 50 Gb/s case, the two receivers manifest similar performances and DSP-induced hardware complexities, making both feasible solutions for real deployments, and after 20 km fiber transmission, an optimum power budget of 20.3 dB is achieved for the 4-level pulse amplitude modulation (PAM4) system.