The investigation on 40G long reach coherent passive optical network

In this paper, the system scheme of the 40G long rich coherent PON is stated and the performance of this PON system has been investigated. Based on the analysis of the requirements for NG-PON and the characteristics of various potential NG-PON schemes, it is believed that 40G PM-QPSK coherent PON will be one of the most promising candidate NG-PON schemes for different application scenes in the near future. Since the coherent received PON is the reliable solution for the far future to satisfy the requirements of ultra-high capacity, higher split ratio, and dynamic access distance. The key performance of 40G bps transmission in the downlink and 10G bps transmission in the uplink are also described to certify the rationality of the system.