Research Of The Caching And Power Control Algorithm For Video Streaming File Based On Opportunistic Cooperative MIMO

With the development of technology,the requirements of online video playback application on wireless system are getting higher and higher.People put forward higher requirements on the video data transmission rate and the quality of video streaming.At the same time,there will be a lot of consumption in video streaming of the user terminals,it brings much pressure to the core network and the radio access network.Cache-enable opportunistic cooperative MIMO for video streaming in wireless systems can effectively solve the difficulty.It can change the topology of the wireless network,and effectively reduce the bandwidth consumption.So as to reduce the burden of network and improve the service quality of users.In this paper,we research a novel solution framework,namely the cached-enabled opportunistic CoMP.The system bandwidth can be effectively saved through equipping caches in the relays and caching a part of the video files in the caches.Firstly,it studied a joint optimization of power and cache control to support real-time video streaming.Then,based on the study of an admissible control policy,and the power control optimization can be figured out with the solution of approximate bellman equation.It is proved that the proposed policy has a better performance of video streaming with the same transmit power.Next,the closed form approximation for the cache optimization problem is deduced and it is solved by a stochastic subgradient algorithm.At the same time,the genetic algorithm is proposed to solve the cache optimization problem.The queue dynamics and video streaming performance are analyzed.The performance metrics of video streaming is figured out by properly scaling the playback buffer queueing system.The performance of video streaming under the policy of MDS-coded random cache and the naive cache scheme are compared.And then,it studied the impacts of average transmit power and the overflow probability under WF(Water-filling)power control and PCI(partial channel inversion)power control.Finally,the impacts of the charging frequency and the average charging delays under the condition of different playback buffer thresholds.