Research On Cooperative MIMO In Wireless Sensor Networks

Wireless Sensor Network has been widely used in the national economy and security as anew information acquisition technology, and in recent years, it is attracting more attention.WSN consists of a large number of nodes, but energy of each node is quite limited, so raiseenergy efficiency become the key question of designing WSN. Cooperative MIMO couldraise energy efficiency of WSN by using redundant nodes, the cluster-head node selectionmechanism and clustering mechanism to form the virtual array. WSN hierarchical routingprotocol is improved from the viewpoint of energy saving, and then combined withcooperative MIMO. The following aspects are researched in this paper:Firstly, routing protocols of WSN are researched in this paper, design principles ofrouting protocols are summed up, classic routing protocols and classic application mode ofMIMO technology based on STBC and V-BLAST are analyzed and compared, and theiradvantages, disadvantages are summed up.Secondly, Grid-LEACH algorithm is proposed by introducing the virtually dividingnetwork into LEACH protocol which has shortages of uneven distribution of cluster-headnodes and blindness selection of cluster-head node. The algorithm is that select cluster-headnodes in subnet according to geography information and residual energy information of nodes,enables cluster-head nodes and network energy consumption evenly distributed, and achievesthe purpose of prolongation network life.Thirdly, Grid-LEACH-MIMO algorithm is proposed from energy-saving angle in thispaper. It can improve the energy-efficiency of WSN and prolong the work-time of net, itcould transfer date via the net-nodes which is mainly Cluster-head nodes and cooperativenodes in the partition of the sub region selected by the set distance and energy thresholdvalues. An energy-model of this algorithm is constructed by analysis and experimentsimulation of the WSN and the model of cooperative MIMO system, then the relationbetween the distance of data transmission and the number of collaboration nodes when the energy consumption is the lowest. The result of simulations shows that the algorithm has anice property in the energy consumption of network, network load balance and datatransmission rather than LEACH and Grid-LEACH, thus the overall performance of WSN isimproved.Finally, the major work of this paper is summarized and further research direction isdiscussed.