Research And Simulation On MAC Protocols Of Ultra-short Wave Networks

As an important way of wireless data communication, ultra-short wave communication has various merits such as high communication quality, simple equipment, building network conveniently and recovering easily when confronting emergency, etc., and is widely used in both military and civilian. Moreover, ultra-short wave communication plays an important role in the field of military wireless communication, and has become a leading way of tactical command communication. The warfare style and scale are always changing with the constant evolution of war type and the emergence of high-tech equipment, and thus makes the bandwidth resource become one of the bottlenecks of ultra-short wave communication. Therefore, it is a great practical significance to study MAC (Media Access Control) layer of the ultra-short wave network.Existing MAC protocols in ultra-short wave network can be divided into distribution-based protocols, contention-based protocols and hybrid protocol.s CBPMAC/TFC, a hybrid MAC protocol combined with FDMA, TDMA and CSMA/CA mechanism, applies for network environment where burst and periodic signals coexist. In terms of low throughput and high energy consumption of the slot allocation strategy within a cluster of CBPMAC/TFC protocol, we propose a centralized TDMA protocol based on request and piggyback and simulate the new protocol on the OMNeT++ platform.The main contributions of the paper are as follows.Firstly, we propose a new MAC protocol for ultra-short wave network named RP-TDMA (Request and Piggyback TDMA). RP-TDMA protocol uses request and piggyback strategies to occupy timeslots, which can effectively reduce contention between nodes and improve system performance.Secondly, the paper analyzes the RP-TDMA protocol performance. We build the RP-TDMA protocol performance model based on the G Bianchi model, analyze the performance of the protocol, and obtain the formulas of throughput and energy consumption.Thirdly, we build a simulation model of ultra-short wave physical layer channel. We build the simulation model of ultra-short wave physical layer channel in MATLAB/SIMULINK toolbox and make a comparative analysis of the simulation results of channel model under different interference.Finally, we build a simulation model of RP-TDMA protocol in OMNeT++ platform, and use Simulink-OMNeT++ co-simulation to simulate protocol model and channel model. Simulation results show that: 1) compared to the CBPMAC/TFC protocol, RP-TDMA protocol can improve throughput and reduce energy consumption; 2) theoretical results of RP-TDMA protocol are basically in line with experimental results of that, which verifies the correctness of performance model of RP-TDMA protocol; 3) the underlying physical channel simulation results have non-ignorable impact on the upper protocol performance simulation results, and the simulation accuracy of the physical layer channel affects the simulation accuracy of upper layer protocol.