Investigating Suitable Multiple Access Techniques for Harbor Wireless Communication Systems

Abstract

The multiple access communications for harbor environment are suffering from both low quality transmission due many metallic obstacles and overloaded networks due to the huge number of users/devices of logistic monitoring. This paper proposes a coded random access (CRA) scheme with a degree distribution suitable for harbor environment to serve many devices and provide communications with high reliability. The degree distribution is optimized using extrinsic information transfer (EXIT) charts by keeping that two EXIT curves do not intersect at low mutual information points. Since we are working on the network level, of which the benefit of broadband communications is kept for the fairness with the narrowband transmission, we convert the gain of broadband transmissions into an equivalent gain to the narrowband transmissions based on the Shannon channel capacity and coding theory. We then compare CRA to carrier sense multiple access with collision avoidance (CSMA/CA), because CSMA/CA has better performance compared to other techniques, such as ALOHA and Slotted ALOHA. We evaluate the performance of the proposed CRA and CSMA/CA using a series of computer simulation in additive white Gaussian noise (AWGN) and multipath Rayleigh fading channels in terms of throughput and packet-loss rate (PLR). The results confirmed that CRA with the proposed degree distribution is more suitable than CSMA/CA as a multiple access technique for harbor wireless communications, indicated that the proposed CRA has higher throughput and lower PLR. The results of this study are expected to contribute to the development of future harbor communication systems.