Spetral-Energy Efficiency Tradeoff In The Indoor-outdoor Separated Scenario For 5G Network

Nowadays, as the Long Term Evolution (LTE) systems are expanding and deploying across the world, we are entering the 4G mobile communication era. It will provide higher quality and richer consumer experience, e.g., real-time mobile video, online games, high definition video transmission services and so on. However, some problems are emerging with the explosion of trillions of terminals and data traffic for 4G, for instance, spectrum crisis, high energy consumption, and unsuitable for high-mobility scenarios like high-speed train and other special communication scenarios. Hence, demand for the next generation wireless communication network is extremely urgent to obtain higher capacity, higher spectral efficiency and higher energy efficiency, enhanced cell average throughput, reduced latency, seamless coverage and accommodated to some special scenarios like, high-mobility scenarios, as well as supporting trillions of devices.As early as 2012, the European Union has already started the research on the 5G, while China has established the IMT-2020 promotion group in 2013 to launch the research work of 5G. In the current domestic and foreign country mobile communication research projects, great improvements of the capacity, spectral efficiency and energy efficiency are proposed as key performance indicators of 5G. To increase the channel capacity and spectral efficiency, the mainstream consensus is to use dense small cellular and seek for higher spectrum, that is, as far as possible to increase cell number while reduce the cell size, and the unlicensed new spectrum resources. So is bound to increase energy consumption, which is a big trouble for the network operators. Therefore, how to reduce energy consumption and increase energy efficiency, in the case of increasing the capacity and spectrum efficiency, are research hotspots for 5G.In this paper, the author focuses on the fifth generation mobile communication system network architecture and key technologies. Then he has studied the indoor-outdoor separated scenario network architecture and applied visible light communication technology to study the channel capacity, spectral efficiency and energy efficiency, and the tradeoff between spectral efficiency and energy efficiency. Firstly, the paper has introduced the research status of mobile communication system both in China and abroad, and the potential key technologies and architecture of the fifth generation mobile communication system. Secondly, the development, advantages, principles and applications of massive MIMO and visible light communication technology are introduced. Thirdly, an indoor-outdoor separated scenario network architecture is proposed to reduce the penetration loss of buildings, further, the spectral efficiency, energy efficiency and the tradeoff between them are studied as well. Finally, the detailed theory of this system is deduced and the numerical simulations are presented.