Multimedia Sensor Network In Sensory Information Compression And Transmission Technology Research

Wireless multimedia sensor network (WMSN) is an advanced form and importantbranch of wireless sensor network (WSN). It imports images, audio, video and othermultimedia information-aware processing functions on the basis of traditional sensornetworks. WMSN combines with WSN and multimedia processing technology. It has abroad application prospects in real-time monitoring, national defense, military affair,commerce, civil field and so on.Because it can capture images, audio, video and other multimedia information,WMSN not only brings rich awareness information, but also increases the complexity ofnetwork processing and transmission tasks. Therefore, it is necessary to developresearch on high-efficient multimedia information transmission technology in WMSN.This dissertation focuses on the key issue of sensing s compression andtransmission in WMSN. The main topics are as follows:1. A DCT-based multi-nodes cooperative image compression scheme(DCT-MCIC) in WMSN is presented for characteristic of resource-constrained, such asenergy, processing, storage capacity and so on. This method makes use of theprocessing capacity of multimedia and normal sensor nodes. The complex imagecompression task is shared with normal sensor nodes instead of multimedia sensor node.Simulation results show that the algorithm not only has a good image quality, but alsoreduces network energy consumption to prolong the network life time.2. Collateral multi-path interference is caused by the broadcast characteristic ofwireless channel. It becomes one of the primary problems of multi-path routing protocolin WMSN. An interference avoidance multi-path routing protocol based on virtual grid(IAMVG) is proposed to avoid it. Firstly, the monitoring area is divided into virtual grid.Secondly, the non-interference grids have been chosen. Finally, cluster head nodes inthe non-interference grids have joined in the routing. Through the approach, the distanceamong links is been pulled as much as possible. As a result, the interference has beenreduced or avoided. Simulation results show that the algorithm can provide QoS quality,such as higher collateral-received-ratio and lower end-to-end delay. 3. In WMSN s cluster routing protocol, the phenomenon of un-uniformlydistributing clusters causes high network energy consumption. Against this, apotential-based clustering routing protocol (PCRP) has been proposed. The routingprotocol is established by the technology of creating potential based on hop and energyconsumption, clustering based on potential, the adaptive power of routing nodes, andrelay nodes transmitting. Simulation results show that the distribution of clusters iswell-proportioned. It balances the network energy consumption and improves the QoSquality, such as network lifetime and reliability.