Synchronization, identification, and signal detection for underwater photon-counting communications with input-dependent shot noise
Abstract
Photon counting (PhC) is an effective detection technology for underwater optical wireless communication (OWC) systems. The presence of signal-dependent Poisson shot noise and asynchronous multi-user interference (MUI) complicates the processing of received data signals, hindering the effective signal detection of PhC OWC systems. This paper proposes a novel iterative signal detection method in grant-free, multi-user, underwater PhC OWC systems with signal-dependent Poisson shot noise. We first introduce a new synchronization algorithm with a unique frame structure design. The algorithm performs active user identification and transmission delay estimation. Specifically, the estimation is performed first on a user group basis and then at the individual user level with reduced complexity and latency.We also develop a nonlinear iterative multi-user detection (MUD) algorithm that utilizes a detection window for each user to identify interfering symbols and estimate MUI on a slot-by-slot basis, followed by maximum a-posteriori probability detection of user signals. Simulations demonstrate that our scheme achieves bit error rates comparable to scenarios with transmission delays known and signal detection perfectly synchronized.
Document Type
Journal Article
Date of Publication
1-1-2025
Publication Title
IEEE Transactions on Communications
Publisher
IEEE
School
School of Engineering
Funders
National Natural Science Foundation of China (62571137, 62231010, 62501381) / Natural Science Foundation of Shanghai (24ZR1407100)
Copyright
subscription content
Comments
Li, F., Zhou, X., Chen, Y., Ni, W., Wang, X., Niyato, D., & Hossain, E. (2025). Synchronization, identification, and signal detection for underwater photon-counting communications with input-dependent shot noise. IEEE Transactions on Communications, 74, 2595–2611. https://doi.org/10.1109/TCOMM.2025.3647758