BICM-ID with Physical Layer Network Coding in TWR Free Space Optical Communication Links

Computers

Alaa A. Saeed Al-Rubaie¹  Zina M. Hassan Abu Almaalie²  Zabih Ghassemlooy² 

[1] Engineering Department, Directorate of Reconstruction and Projects, Ministry of Higher Education and Scientific Research, Street 52, Al-Rusafa, Baghdad 55509, Iraq;Optical Communications Research Group, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, U.K.;

关键词: physical layer network coding;    free space optical communication;    bit interleaved coded modulation with iterative decoding;    turbulence-induced channel;    Monte Carlo simulation;    ExIT charts;   

DOI  :  10.3390/computers6030024

来源: DOAJ

【 摘 要 】

Physical layer network coding (PNC) is a promising technique to improve the network throughput in a two-way relay (TWR) channel for two users to exchange messages across a wireless network. The PNC technique incorporating a TWR channel is embraced by a free space optical (FSO) communication link for full utilization of network resources, namely TWR-FSO PNC. In this paper, bit interleaved coded modulation with iterative decoding (BICM-ID) is adopted to combat the deleterious effect of the turbulence channel by saving the message being transmitted to increase the reliability of the system. Moreover, based on this technique, comparative studies between end-to-end BICM-ID code, non-iterative convolutional coded and uncoded systems are carried out. Furthermore, this paper presents the extrinsic information transfer (ExIT) charts to evaluate the performance of BICM-ID code combined with the TWR-FSO PNC system. The simulation results show that the proposed scheme can achieve a significant bit error rate (BER) performance improvement through the introduction of an iterative process between a soft demapper and decoder. Similarly, Monte Carlo simulation results are provided to support the findings. Subsequently, the ExIT functions of the two receiver components are thoroughly analysed for a variety of parameters under the influence of a turbulence-induced channel fading, demonstrating the convergence behaviour of BICM-ID to enable the TWR-FSO PNC system, effectively mitigating the impact of the fading turbulence channel.

【 授权许可】

Unknown