Research On Cross-Layer Of Wireless Mobile Multimedia Sensor Networks Route

Wireless Mobile Multimedia Sensor Networks (wireless mobile media sensor networks WMMSNs) is a novel Wireless Sensor Networks (Wireless Sensor Networks WSNs),which are composed by audio and video capture device as the sensor and sensor nodes attached with mobile devices to information acquisition on moving objects. WMMSNs main content of information acquisition including video, audio, image and other multimedia information, the node region random mobile in the specific monitoring, the mobile node can broaden the field data collection, enrich objects (such as moving target) of information acquisition. However, mobile nodes can cause the network topology dynamically changes, wireless channel quality is not enough stable problems. In addition, WMMSNs have several characteristic such as heavy network traffic, high transmission energy consumption, end to end delay requirements strictly, packet loss rate and so on, these characteristics increase the difficulty of WMMSNs routing protocol research, and affected the further promotion of WMMSNs.Scholars at home and abroad have conducted a lot of research on routing protocol of WMMSNs. They found that the traditional hierarchical protocol design will be difficult to optimize the performance of the network. First of all, the traditional hierarchical structure design is oriented to the wired network, wired network nodes are static, network topology is relatively fixed, link quality is relatively stable, however WMMSNs channel unreliable, network topology frequently changes and the nodes in a specific area moving at the same time for data collection and transmission, adopts a hierarchical structure will seriously affect the WMMSNs performance; secondly, in order to optimize the performance and improve the efficiency of the network in the WMMSNs, nodes need to use multiple layers of relevant parameters frequently, which requires exists the channel of communication parameters between the different layers. To solve this problem, researchers using cross layer approach to design the routing protocol of WMMSNs, to strengthen the information interaction between different layers and optimize the overall performance of the network. But the current routing protocol based on cross layer still exists some problems:single path transmission is used in data transmission, this will increase network end to end delay and reduce the network throughput, increase the load on the single path; routing protocol choice the routing metric to construction path less use link quality and residual energy as a routing metric. This will reduce the success rate of data transmission, increasing the packet retransmission times; multimedia network has large amount of communication flow, exists a lot of coding opportunities at the data transmission process, and existing routing protocol rarely were detected network coding opportunities. In this paper, to solve the problem of WMMSNs routing protocol research, the main research work is as follows:(1) This paper introduces the concept and characteristics of WMMSNs, point out the challenges on the research of WMMSNs routing protocols, such as:topology dynamic change, link quality is not stable, time delay sensitivity, etc., summarizes the routing protocol design should follow the principles (reliability, real-time and energy efficiency) in WMMSNs reviewed the needle for several routing protocols proposed WMMSNs, analysis and pointed out that the advantages and disadvantages of these protocol, this paper is presented necessity of cross layer design in WMMSNs.(2) The cross layer design of WMMSNs is described, and the concept and characteristics of cross layer design are introduced. The model and principle of cross layer design are analyzed, and several cross layer routing protocols are introduced in this paper. The cross layer protocol working principle and working process are analyzed, and points out the shortcomings of route protocol.(3) A cross layer model of RCLF is designed. The RCLF cross layer model is composed of RC components and LF components. RC components, on the one hand provide parameters for node access control, on the other hand, according to the time delay of the network layer, link quality of link layer, and the residual energy of the nodes in the physical layer to calculate the link weights, then provide the weights of link to network layer. During the process of data transmission, the LF component increases the power of physical layer or notify network layer about routing failure, LF component can reduces the number of routing reconfiguration when the path is interrupted or the link is migrated.(4) A cross layer coding aware multipath routing protocol (MRCC) is proposed. The MRCC protocol uses the RCLF cross layer model to optimize the routing construction. The work flow of MRCC protocol as follows:if nodes want to construct route path, the source node broadcasting RREQ message, the node who received RREQ message will based on the residual energy of nodes in the RC components determines whether to join the path construction(i.e. access control). If the node meet the access conditions, RC will based network layer, data link layer and physical layer parameters calculation the link weights, and feedback to the network layer routing construction as a criterion, else directly discarded RREQ message; when the destination node received RREQ message will through unicast reply RREP message, and then establish the node disjoint multipath link between the source and target nodes, and divide the data stream into multipath transmission In the process of data transmission, the node carries on the monitoring of the coding opportunity, once the coding opportunity is detected, the data is transmitted through coding.In order to verify the proposed routing protocol, this paper use OMNeT++ network simulation platform to simulate MRCC protocol, Setting different parameters in the simulation process to observe the performance, at the same time, two existing routing algorithms are selected to compare with the proposed routing protocols, which verify the effectiveness of the proposed routing protocol. Simulation results show that the MRCC protocol can reduce the routing overhead, guarantee the reliable data transmission and reduce the end-to-end delay.