Research On Wireless Network Capacity Based On Physical Layer Network Coding Under

Capacity of wireless networks has become an important research direction because the capacity is often used as an important criterion of wireless network performance in real-world applications. However, the issues of network capacity expansion is a fundamental problem of wireless networks capacity. The average capacity of each network node will tend to zero when the number of nodes in the network increases large enough. Therefore, the size of the wireless network nodes is limited. To get rid of this restriction, researchers do all aspects of work to give the wireless network scalability by improving network capacity. PNC, as an extension of network coding, can enhance the capacity of wireless networks by reducing interference between wireless network nodes. Previous researchers have studied the capacity of wireless networks based PNC under protocol interference model. But protocol interference model had only affected one node without considering the impact of the global node, and there is only one parameter Δ that cannot express the true good network environment. SINR model that is more in-depth analysis of the interference and conforms to the actual environmental conditions of the wireless network is now widely used in the capacity research as it considers the node transmitting power, path loss, white noise and the influence of all nodes.To overcome this shortcoming, this thesis presents a method of single-hop and multi-hop wireless network capacity evaluation based PNC under SINR. Specific arrangements are as follows.(1) For the single-hop wireless networks, finding concrete expression of the wireless network capacity according to the Maximum flow minimum cut theorem, and draw out the characteristic curves of the wireless network capacity following with the common transmission, the traditional network coding and physical layer network coding programs with node transmission radius dr, path attenuation factor α, SINR threshold β, sending white noise power ratio N/P. Analysis showed that the characteristic changes, PNC scheme can greatly enhance the capacity of wireless networks, while can derive the characteristics of impact on the network capacity and the impact caused by the various parameters of SINR.(2) For the multi-hop wireless network, getting the best compromise in wireless network capacity and delay in. Deduced wireless network throughput and latency of expression by establishing a network model, definiting transmission and routing scheme. We validate the correctness of the theory through a simulation of wireless network throughput and latency according to the theory of M/M/1. Such as single-hop wireless networks, drawing out the characteristic curves of the multi-hop wireless network capacity to verify the correctness the theory. Simulation results show that capacity of multi-hop wireless network based on PNC under SINR can still achieve a good improvement.