Research On Adaptive Power Control And Routing Algorithm In Mobile Cognitive Networks

Cognitive networks are widely used in commercial, military, industry and other fields for its self-organizing, self-configuring and self-aware. However, the limited resource, the channel interference and dynamic topology in cognitive networks make the network protocols designed by traditional hierarchical have poor performance. Al-though traditional layer reduces the complexity of network design, it has inefficiency information exchanged between each layer which make it can not take advantage of the limited channel resources and power resources. Cross-layer design utilizes the informa-tion between each layers and consider the network as a whole, which make it become a great potential technology to improve the performance of cognitive networks.In this dissertation, for the multi-channel and multi-hop characteristics of cog-nitive network, the routing algorithms and power control in cognitive networks are explored and researched according to the cross-layer design. To reduce the delay and packet loss ratio and improve the throughput of networks, it joints the routing algo-rithms and adaptive power control. At the same time, it also takes into the factors of node mobility, channel association and channel interference account to provide the design and implementation of routing protocol based on mobile cognitive networks. Main contributions of this paper are summarized as follows.● In the paper, the problem of jointing adaptive power control and routing algo-rithm in mobile cognitive networks have been formally described, which is trans-formed into a non-linear mixed-integer programming model. On this basis, the paper models the mobile cognitive networks, and provides network model, prob-ability model, mobility model and channel interference model.●Based on the characteristics of cognitive networks, the paper proposals the method that joint adaptive power control and routing algorithm. In cognitive networks, power control is generally used to control the topology and save energy. How-ever, this paper novelly take both adaptive power control and routing algorithm into account. In this way, nodes select the next node by predicting mobility and channel interference, which make the route more stable and anti-interferential.● The paper modifies the NS2 simulator to support the requirement of multi-channel and adaptive power. The new NS2 is able to control power and select the suitable channel through the cooperation of physical layer and MAC layer. A number of experiments indicate that the method proposed in the paper is able to apparently increase the throughput of the network and ensure the relatively low delay and package loss ratio.