Performance Analysis Of Large Scale Virtual MIMO Systems

Cellular mobile communication network is an important part of the information high-way in our country, playing an important role in our country’s development. With the development of mobile Internet and Internet of things, rapid growth in demand for wire-less communication is urgent. In order to cope with business growth and guarantee the sustainable development of mobile cellular networks, improving the network capacity and energy efficiency is the key problem to be solved. MIMO can effectively improve the en-ergy efficiency of wireless communication system and (or) spectrum efficiency by means of equipping with multiple antennas at both ends of the wireless link respectively.but as a result of limitation of the size of the terminal equipment, the advantages of MIMO tech-nology is restricted. By means of using multi-user distributed collaboration to simulate a MIMO system, virtual MIMO (V-MIMO) breakthroughs the limitation of the terminal antenna number, and is expected to get a higher gain under the architecture of cellular networks.The technology of V-MIMO can both improve the energy efficiency and spectral effi-ciency. Understanding the tradeoff relationship between EE and SE can help us knowing the performance limit of the MIMO technology, which can guide us to design and optimist the MIMO system. In the present large scale virtual MIMO cellular system, it’s unclear the relationship between EE and SE, which is a natural contradiction. To the end, based on the uplink of multi-user cellular system with decoding forward, this paper studies the re-lationship between EE-SE tradeoff. Firstly, we deduce the general implicit function which describes the relationship between EE and SE. Secondly, we deduce the closed expression of EE-SE tradeoff in high SE and low SE respectively, and propose a heuristic method of resource allocation which can optimize the EE-SE tradeoff. Through a number of theo-ries and number results, we research the influence of the relationship of EE-SE tradeoff changing with the different space density of the end users, the space density of base station and the different parameters of decode forward protocol. Comparing with the traditional MIMO system, we found that under different scenarios, V-MIMO system is not always beneficial to the performance of system, but only plays in a certain range of SE. It’s helpful to reduce spectrum reuse rate, dynamic resource allocation and controlling the density of users for improving the performance of V-MIMO cellular system.