Research On High Dynamic Networking Technology Based On Time Division Multiple Access

In the multi-hop wireless network,due to the broadcasting feature of the wireless channel,there exists transmission interference between the nodes in the network.As the number of nodes increases,the transmission interference will also increase and have a bad influence on the network performance such as throughput.Thus,an efficient MAC protocol is needed to coordinate the transmission between nodes.Traditional MAC protocol contains two major implementation categories: Carrier Sensing Multiple Access(CSMA)and Time Division Multiple Access(TDMA).Because of the random transmission feature of CSMA,it has some drawbacks such as low throughput under heavy traffic.Previous research has shown that TDMA protocol has more stable throughput performance,which is widely applied in military field and rescue missions.In such situations,the network topology may change frequently,that is,the number of nodes existing in the network varies from time to time frequently.Traditional protocols suffer from low throughput under high dynamic environments.Hence,this paper proposes a novel MAC protocol based on TDMA and we compare our protocol with existing approaches in throughput,control message and network join time aspects.The result shows our protocol gains more throughput,less control message redundancy and faster network join time than the traditional protocols in high dynamic networks.This paper introduces some basic concepts and knowledge about the wireless network and explains the basic principle of the protocols.Furthermore,we summarize the current research background and analyze the detail implementation of scheduled-based TDMA and contention-based TDMA protocol.A frame structure with fixed length is proposed in this paper.Based on the structure,we set up the relationship between the nodes and the slots.Furthermore,we come up with a network join procedure.Additionally,we design a combinational slot access mechanism containing fixed slot access and idle slots contention-based access,which increases the utilization of the idle slots.Meanwhile,we prove the fairness and collision-free feature of our protocol and make some theoretical analysis in throughput,control message and network join time aspects.This paper explores the current simulation tools and summarize the main features of them.Based on the knowledge,we analyze the basic structure of OPNET and set up the model of our protocol and the existing approaches.We do the simulation in three aspects: control message,throughput and network join time.The results show that our protocol gain more throughput and decrease the redundancy of the control message.Furthermore,the network join time is also be optimized.