الفهرس | Only 14 pages are availabe for public view |
Abstract 5G is an emerging mobile generation that has a lot of enabling technologies, one of the most enabling technologies is the IoT (Internet of Things). Things are communicating to each other over the internet. MTC (Machine Type Communication) is the enabling technology for IoT. Machine-to-Machine Communication (M2M) is the communications between wireless devices without human interventions. As a fundamental enabler of Internet of Things, M2M is growing fast and implemented in many areas. The number of M2M devices is expected to be extremely large in the future. In most cases they are battery driven and positioned in broad areas so that it would be costly to frequently replace or charge their batteries. To save the cost of maintaining M2M systems in the long term, energy consumption needs to be minimized so that battery lives of M2M devices can be maximized, which motivates the design of a low power MAC protocol in this thesis. The related works have indicated that idle listening and collisions are the main sources of power waste. In the proposed low-power MAC protocol design, various methods that would help preserving energy are considered. First the performance of three conventional protocols, TDMA, CSMA, and reservation-based protocol were analyzed. The packet delay, energy consumption, network lifetime, and system throughput performances of these protocols are evaluated with both theoretical analysis and numerical simulations. Our results show that CSMA has better packet delay and throughput performances while static and dynamic TDMAs are more energy efficient. Then we design a Multi-layer based CSMA/CA protocol for cellular based system to show that adding multi-layer concept will reduce energy consumption and hence increase network lifetime Furthermore, a hybrid ML-CSMA/TDMA energy-efficient MAC protocol for M2M communications was designed. Simulation results showed that the proposed MAC protocol outperforms the traditional CSMA/TDMA hybrid protocol in energy saving. With Abstract_______________________________________________________________ V the proposed MAC protocol, the lifetimes of both individual nodes and the whole M2M network are significantly extended. |