Research On Optimization In Multi-Hop Wireless Networks Based On Network Coding

With the development of Multi-hop wireless network, people can set up a networkanytime and anywhere, for its good reliability and scalability, it’s more and more important inmodern communications. Its self-organizing, self-configuring, self-healing, and many otherfeatures make it to have a faster speed of deployment, easy to maintain, lower cost, goodreliability and scalability. A variety of network forms like Ad hoc networks, wireless sensornetworks and wireless Mesh network have been widely used in military, civilian and otherfields.Network coding is effective to improve the network performance. Combined with thebroadcast properties of radio channels, a relay node can send more information to others in atransmission, and reduce the numbers of data sending to improve network throughputultimately. In addition, network coding can also balance the network load, improve bandwidthutilization, and improve the robustness and security of the network.It is worthy to study that how to discover more coding opportunities in a node. Morechances in a node mean that we can use the network coding to improve network performanceas much as possible. Based on the analysis of the general network coding conditions, in thisarticle, we propose ExCODE, a new strategy to discover all opportunities in relay node.Through appending the additional information to a packet, it can enable the relay node todiscover the potential coding opportunities as much as possible. ExCODE is really a real-time,efficient method to discover coding chance in a node. Finally, we take ExCODE in tosimulation, experimental results show that the algorithm has a very good effect to improvingnetwork throughput, reducing end to end delivery, and increasing packet delivery ratio.Simulation results prove the viability of it.Based on the ExCODE, we then proposed Ex-CAR in this article, a coding-awarerouting protocol with considering coding opportunities to maximize in all nodes. It selects abest node in the forwarder set to encode the packets and then forward it, through consideringthe number of coding chance in each node. The best node has the most coding chance toexecute network coding operation for certain packet in current forwarder set. It result in themost information can be transmitted in a procession of sending, and improve network throughput ultimately. Similarly, we take this strategy in to simulation, experimental resultsshow that the proposed algorithm is useful to improving network throughput and increasingpacket delivery ratio. Simulation results prove the viability of Ex-CAR.