Interplay of Probabilistic Shaping and the Blind Phase Search Algorithm

Author(s)

Mello, Darli A. A. ^[1] ; Barbosa, Fabio Aparecido ^[1] ; Reis, Jacklyn Dias ^[2]

Affiliation

^[1] Univ Estadual Campinas, Sch Elect & Comp Engn, BR-13083970 Campinas, SP - Brazil

^[2] Idea Elect Syst, BR-13080650 Campinas, SP - Brazil

• Document type: Journal article
• Source: Journal of Lightwave Technology; v. 36, n. 22, p. 5096-5105, NOV 15 2018.
• Web of Science Citations: 4

Abstract

Probabilistic shaping (PS) is a promising technique to approach the Shannon limit using a typical constellation geometries. However, the impact of PS on the chain of signal processing algorithms of a coherent receiver still needs further investigation. In this paper, we study the interplay of PS and phase recovery using the blind phase search (BPS) algorithm, which is widely used in optical communications systems. We first investigate a supervised phase search (SPS) algorithm as a theoretical upper bound on the BPS performance, assuming perfect decisions. It is shown that PS influences the SPS algorithm, but its impact can be alleviated by moderate noise rejection window sizes. On the other hand, BPS is affected by PS even for long windows because of correlated erroneous decisions in the phase recovery scheme. The simulation results also show that the capacity-maximizing shaping is near to the BPS worst-case situation for square-QAM constellations, causing potential implementation penalties. (AU)

• FAPESP's process: 15/24341-7 - New strategies to confront with the threat of capacity exhaustion
• Grantee: Helio Waldman
• Support type: Research Projects - Thematic Grants
• FAPESP's process: 15/24517-8 - Photonics for next generation internet
• Grantee: Hugo Enrique Hernández Figueroa
• Support type: Research Projects - Thematic Grants