Researches Of Load-Balancing Routing Algorithm In Vehicle Ad-Hoc Networks

With the repid development of wireless communication technology, vehicle Ad-Hoc network which is a traffic warning and a new application model of accessing to Internet is becoming the one of the research hottest spots in academic and industrial sectors in recent years. VANET combines data collection, processing and wireless communication, and it has a characteristic of environmental self-adaptive. Due to the increasing the number of vehicle, as well as the people keeps the demand for information, VANET has broad application prospects. VANET which is large scale, large number of nodes, unevenly distributed nodes and fast-moving nodes, will lead to change in network topology frequently and shorten the life of links. How to fully esploit the potential of the network and ensure the real-time, effectiveness of network services is a foundation for real application. The research on VANET Routing Mechanism has gread significance.According to the current vehicle routing algorithm, the network mechanisms of load balancing are inadequate, applying heterogeneous and multi-layer's Wireless Mesh Network structure into VANET, the multi-layer and clustering network structure is proposed. Making use of location information which come from GPS in vehicle, event driven, congestion monitoring and routing mode switching, we design a network load-balancing routing protocol. By defining the forward nodes set, every node collects the information of two hops neighbors and forms a nodes set in which member can monitor each other, this will be helpful to solve the "hidden terminal" problem. When the network connectivity is poor, the routing protocol will switch to opportunistic routing mode, through the position information and speed information of neighbor nodes, the opportunistic routing mode will calculate the location of its neighbors will be, and then determining the basement node and forming the forward nodes set. Rely on load-balancing, routing mode switching, forward nodes set multicast mechanism to ensure the QoS when the network connectivity is poor or heavy load.Network coding is a new routing mechanism, it allows intermediate nodes to participate in the handing of message and improves the network throughput. In-depth analysis of network coding mechanism, and then putting it into VANET, nodes according to the local topology information, combine with the maximum distance separable (MDS) code to determine the different data sending rate, at the same time, node calculates the minimum finite field and chooses the element which is not zero from the minimum finite field to construction the global coding matrix, and sends the column vector of the global coding matrix to downstream node to guide the intermediate nodes to encode, this will ensure that the global encoding matrix satisfys certain linear independent features, and the destination node will successfully decoded. This will help to deduce the amount of communication redundancy and ensure the decoding efficiency.The simulation results of the new algorithm in delay, throughput performance show that the new algorithm is more effective in reducing the number of nodes in communication and reduce communication interference, balanced network load and fully exploit the potential of the network.