Research On Application Of Network Coding In Cooperation Communication

Comparing to wired channel, the wireless channel has the fading characteristics, which havegreat effect on the transmission rate and quality of the signal. Cooperative communication has beenproved to be against the fading characteristics effectively. However, the utilization of spectrum incooperative communication is low. The introduction of network coding in cooperativecommunication can improve the spectrum utilization. So the research on the application of networkcoding in cooperative communication has been a hot area in recent years.Firstly, in this thesis, the relevant theoretical knowledge is introduced, including thecharacteristic of wireless channel, cooperative communication and network coding. For networkcoding, based on the researches of the basic idea, common system models and coding methods, therelated researches on the security of network coding are introduced, and the mainly security threatsare wiretap and byzantine attacks.Secondly, the concept of security capacity is introduced, which can be the performance criteriaof the wiretapped network coding. In the high SNR regime, the approximate formula of secrecycapacity is derived. Then through detailed computer simulation, the effect of node’s location on thesecrecy capacity is evaluated.Finally, a hybrid transmission strategy is presented, which is based on three basic strategies:direct transmission strategy, cooperative transmission strategy and network coding strategy. Therealization method of hybrid transmission strategy is studied under the analog and digital systemrespectively, and the simulation results show that the strategy can improve the capacity of systemeffectively.