Research On Wireless Cooperative Transmission Based On Network Coding

With radpid development of wireless applications and the limited available spectrum resource, serving these applications reliably has become a big problem. Due to the characters of wireless channel, including path loss, shadow and multiple fading, the reliable techniques for communication in wireline network can not be applied to wireless network. However, cooperative communication can trackle these challenges, its basic idea is that wireless nodes work together to achieve their individual goals or one common goal. In cooperative communication, wireless nodes share their resources, i.e., radio link, antenna, etc. The combination of network coding and cooperative communication not only improves the throughput of the whole network, but also provides more reliable communications by using the redundancy of network coding. Hence this combination has drawn great attention from academia and industry.In general, wireless network coding is divided into digital network coding and analog network coding. This dissertation focuses on the cooperative transmission techniques based network coding. It contains three aspects, including single relaying based on analog network coding, single relaying based on digital network coding and multiple relaying based on digital network coding. The main contents and contributions are listed in the following:1) Applying analog network coding to single relaying, we propose a two way transmission protocol based on analog network coding. Wireless cooperative network model is two-way relay channel in cellular network, where every node is equipped with multiple antennas and has multiple data streams to transmit. In this network model, multiple users exchange information with the base station with the aid of a relay.I) Block signal alignment is proposed for this model, and then an analog network coding transmission protocol without interference is designed based on the proposed idea.II) Three algorithms are proposed to minimize the outage probability of each user through the joint design the power control matrice of users, relay and base station. The first two algorithms are to maximize the end-to-end effective channel gain, and the last algorithm is to maximize the end-to-end effective signal to noise ratio (SNR).