Study Of QoS Routing Protocol Based On Energy Constraint In Ad Hoc Networks

Ad Hoc network is a distributed wireless network that can be rapidly deployed in case of emergency. It has been widely used in many fields and has a wide application prospect and great research value in wireless communications.With the increasing demand in audio, video and other multimedia services, QoS Routing Protocol has gradually become a research hotspot in Ad Hoc Networks. In recent years, scholars have raised many routing protocols of this kind and showed their good performances by simulation experiments without consideration of the energy constraint. As the Ad Hoc network is a power limited system, the networks will be interrupted as soon as the energy of the node in Ad Hoc networks has been run out, which has a direct impact on communication. So saving the energy consumption of node and extending lifetime of networks should be considered as important indicators in course of the design of the routing protocol.In order to make use of bandwidth and energy resources of network effectively in Ad Hoc networks, this paper proposes two QoS routing protocols based on energy conservation which are QEC-AODV and QRETP. QEC-AODV is an improved QoS routing protocol based on AODV and energy constraint. The main idea of QEC-AODV is that the nodes of Ad Hoc networks are divided into three different types under the premise of bandwidth in the fully protection, and RREQ received by different type of nodes is disposed with appropriate mechanism for the delay according to the residual energy of nodes in the network. The path with sufficient bandwidth, the most remaining battery energy of node, the least transmission energy will be chosen as the optimum path. QRETP is a QoS routing protocol based on residual energy of node and transmission power of routing in Ad Hoc networks. It meets the QoS requirements of routing protocol by calculating bandwidth of the nodes. Considering the transmission power as well as residual energy of mobile nodes, on one hand, the protocol avoids taking network split as the target and balances the energy consumption of node; on the other hand, it saves the energy of network that is limited.In addition, simulator frames about QEC-AODV and QRETP are proposed in OPNET Modeler to implement QEC-AODV and QRETP. The simulating result shows that QEC-AODV has better performance on networks throughput, average energy consumption of node and lifetime of network than that of AODV when the QRETP slightly increases the delay, the performances of QRETP on lifetime of network, average energy consumption of node and packet delivery fraction are improving in varying degrees which brings better performance in other aspects. Through analysis and comparison of QEC-AODV and QRETP, the performance of QRETP is better than QEC-AODV's as a whole because QRETP can balance energy consumption of node and save energy consumption of networks.The design of QEC-AODV and QRETP protocol in this paper has provided references for the actual system design, which has an important guiding significance.