Study On Multi-hop Relay And Spectrum Allocation For Wireless Distribution Network

With the developing of wireless communication technologies and the emergence of media service, IP and flattening is becoming the main characteristics of the future wireless communication networks, and the distributed wireless multi-hop network is a strong momentum to drive the trend. With the advantages of supporting multi-hopping connection, wide covering range, flexible networking and communication while moving, multi-hop wireless technology is becoming a considerable wireless research aspect. At the same time, multi-hop relay technology is becoming the important support technology of the future distributed wireless network. In view of this, this thesis studied and analyzed the relay technology that based on different time slots forwarding, and selected the best performing forward strategy based on the physical layer network coding, and then proposed an algorithm that applied to any number of relaying forward. In addition, spectrum resource is quite costly for wireless communications. For double channel multi-hop wireless communication system, frequency distribution is performed in network operation, which is able to provide reliability and flexibility. Cognitive radio(CR) technology could realize channel multiplexing in terms of time, frequency and spatial domain because of its higher spectrum utilization. To deal with the dilemma between spectrum congestion and spectrum underutilization, cognitive radio technology has been proposed and advocated, which allows cognitive secondary users to intelligently sense and opportunistically access those spectrum holes temporarily unused by license-holding primary users. In this thesis, we use cognitive radio technology to sense the frequency, and then design a spectrum negotiation mechanism among the user nodes. The main works are listed as follows:(1)Base on the methods of the two-way relay, propose a relay algorithm that applies to any number hops to forwarding. As a theoretical basic for the project implementation, use the software radio peripheral USRP to implement the distributed multi-hop wireless network.(2)To enable the stabiles of network operation, a distributed frequency distribution mechanism is proposed: The distributed frequency distribution mechanism is able to stabilize the network and enhance the reliability of link. The biggest characteristic of this mechanism is that it improves the reliability of the wireless links and the system operation which is based on basic network available.