Researches On Cross-layer Hierarchical Protocol Of Cognitive Wireless Mesh Networks

Through opportunistically using free spectrum resources, cognitive radio (CR)technology can improve the utilization of spectrum band. In recent years, most ofscholars interested in cognitive radio have made their effort to research on the processof spectrum hole dectection, wireless channel assignments and wireless route protocols.However, owing to its complexity, the researchregarding route protocol is lesscomprehensive compared with those foregoing two aspects. Moreover, the few existingresearches on route protocol fail to raise an explicit protection for PU receiver and theresearches on route metrics and the optimization of route algorithm are also limited.Therefore, this paper puts forward a Cross-layer Hierarchical Protocol of CognitiveWireless Mesh Network.Due to the fact that cognitive user cannot afftect the authorized/primary user (PU),the opportunistically utilization of free spectrum band must be properly designed.However, since this affection cannot be avoided in the real communication scenario, atrade off between CR user’s end-to-end performance and the protection of PU receiveris necessary. Aiming to realize the objective, this paper designs a route strategy with twogoals:(1) expliciting protection for PU receiver; and (2) maximizing the CR user’send-to-end performance with acceptable interference.This paper mainly focuses on three aspects as bellows:①Cognitive radio routing strategy. Through massive investigation and survey, thispart analyzes recent researches on cognitive radio routing protocol, and summaries theirmerits and drawbacks. Accordingly, it then raises a Cross-layer Hierarchical Protocolaiming to solve the proposed problems.②Optimization of route metrics and route algorithm. Through massive explorationof relevant documents on wireless cognitive radio route algorithm, this part proposes asolution for hide/exposed node problem, as well as the design and optimization of routemetrics. After that, it develops an optimization algorithm based on its hierarchicaldesign.③Cross-layer Hierarchical Protocol. This part designs a two-demension scenariofor the complex wireless cognitive radio. To be specific, it divides the route protocolinto two main parts: those concerning CR user end-to-end performace route strategy andthose concerning PU receiver protection route strategy, which is tested and verified through simulation for its validatiy and effectiveness.