Downlink Energy-Saving Strategy Research Based On Service In Heterogeneous Networks

With the rapid development of mobile communication technology, the communication network structure is becoming more diverse and complex, the collaboration has become the trend of the development of the next-generation wireless communication systems. Any kind of mobile communication technology won’t dominate the future network, while the heterogeneous wireless network will integrate a variety of radio technologies. The evolution of communication technology has brought unprecedented convenience for us, but are followed with the problem of power consumption which worth our focus as well. In terms of the energy, environment and economic, energy saving has become an urgent problem of communication industry. Aiming at constructing resource-saving and eco-friendly networks, green communications focus on minimizing the power-of-service quality-of-experience.Therefore, the aim of this thesis is mainly devoted to the energy saving problem considering several services under the heterogeneous network environment with multiple current standard networks and caching energy saving problem under the heterogeneous environment with the cellular communication system and devices communication system(D2D). Specifically, the main contents and contributions are summarized as follows.1.We investigate the energy saving problem based on several services under the heterogeneous network environment. According to the current network deployment and the actual power consumption model of evolved base station(e Node B), we develop the algorithm of base station shutoff and user association algorithm considering energy consumption under the heterogeneous network of the Global System for Mobile Communication(GSM), Synchronous Code Division Multiple Access(TD-SCDMA) System and long-term Evolution(LTE). Firstly, we model the resource allocation problem of different services and the model guarantees the services for users resulting in the minimum energy consumption. And we use Hungry algorithm optimize the allocation of network resources. In order to evaluate the algorithm, we build the simulation platform using the key technologies of different networks and combing with real operation data of operators. The simulation results show that the algorithm of base station shutoff and user association algorithm has higher energy gain than the current network access algorithm has.2. We investigate the caching energy saving problem based on the video service under heterogeneous network of cellular communication system and devices communication system. Under a network scenario with one base station and multi-user, the cell is divided into multiple clusters. And D2D communication can only take place within the same cluster. According to the characteristics of video service and the cache capacity of user equipment, we make the model aiming to minimize the energy consumption of content caching and content request. In order to reduce complexity and be easy to realize, we propose the corresponding caching algorithm for energy consumption optimization algorithm, including content caching algorithm and content request algorithm. In order to evaluate the algorithm, using the key technologies of cellular communication system and D2D communication system, we build the simulation platform. Simulation results show that the caching algorithm for energy consumption optimization has higher energy gain and cache hit ratio than random caching algorithms and no caching algorithm.