Novel Relay Selection Algorithms for Machine-to-Machine Communications with Static RF Interface Usage

Machine-to-Machine (M2M) communications have been introduced to improve the communication capacity in dense wireless networks. One of the most important concerns for network designers is maintaining the high performance of the network when the quality of connections between sources and their destinations is poor. Thus the careful selection of relays between data sources and their destinations is a very important issue. The possibility of simultaneous use of different Radio Frequency (RF) interfaces for transmitting data, which communication devices are equipped with them, can increase the capacity of data transmission over the network. In this paper, two novel M2M relay selection algorithms are proposed, named as Optimal Relay Selection Algorithm (ORSA) and Matching based Relay Selection Algorithm (MRSA). ORSA is a centralized algorithm for the optimal selection of relays by transforming the main problem to a k-cardinality assignment problem that can be solved using the Hungarian algorithm. MRSA is a distributed algorithm that leverages concepts from matching theory to provide a stable solution for the relay selection problem. In both proposed algorithms static RF interfaces usage is applied to enable simultaneous use of different interfaces for data transmission. The simulations show that ORSA is optimally solving the relay selection problem. MRSA has an optimal stable result, that when there is no restriction on the number of channels, is only about 1% lower than ORSA. Besides, MRSA provides better results than direct transmission Without any Relay Selection Algorithm (WRSA) and Random Relay Selection Algorithm (RRSA), about 15% and 98%, respectively.Comment: 51 pages, 17 figure

Opportunistic Routing Metrics: A Timely One-Stop Tutorial Survey

High-speed, low latency, and heterogeneity features of 5G, as the common denominator of many emerging and classic wireless applications, have put wireless technology back in the spotlight. Continuous connectivity requirement in low-power and wide-reach networks underlines the need for more efficient routing over scarce wireless resources, in multi-hp scenarios. In this regard, Opportunistic Routing (OR), which utilizes the broadcast nature of wireless media to provide transmission cooperation amongst a selected number of overhearing nodes, has become more promising than ever. Crucial to the overall network performance, which nodes to participate and where they stand on the transmission-priority hierarchy, are decided by user-defined OR metrics embedded in OR protocols. Therefore, the task of choosing or designing an appropriate OR metric is a critical one. The numerousness, proprietary notations, and the objective variousness of OR metrics can cause the interested researcher to lose insight and become overwhelmed, making the metric selection or design effort-intensive. While there are not any comprehensive OR metrics surveys in the literature, those who partially address the subject are non-exhaustive and lacking in detail. Furthermore, they offer limited insight regarding related taxonomy and future research recommendations. In this paper, starting with a custom tutorial with a new look to OR and OR metrics, we devise a new framework for OR metric design. Introducing a new taxonomy enables us to take a structured, investigative, and comparative approach to OR metrics, supported by extensive simulations. Exhaustive coverage of OR metrics, formulated in a unified notation, is presented with sufficient details. Self-explanatory, easy-to-grasp, and visual-friendly quick references are provided, which can be used independently from the rest of the paper.Comment: 41 Pages, 28 figure