The Research And Analysis On Distributed Antenna Stytems

With the substantially growth of wireless communication services, the distributed antenna system has been extensively studied. Compared to traditional cellular network systems, the system reduces distance access, and expanded coverage. At the same time, due to the growing energy demand and rising energy prices, the pursuit of high energy efficiency is becoming the mainstream of the future of wireless communications design. Therefore, this paper mainly discusses the energy efficiency of the distributed antenna system.This paper introduces the general development of wireless communications, and then describes the relevant knowledge, which includes its definition, structure, characteristics and research status. Based on the theory of system model, channel characteristics, diversity and fractional programming, the paper discusses the energy efficiency optimization problem. Further more, the paper proposed the optimal power allocation scheme, which is based on maximizing energy efficiency. Numerical simulations show that the performance from the proposed scheme is better than the equal power allocation scheme. But we still need to search for all combinations of possible solutions in the process of solving the optimal solution. In order to reduce the computational complexity of the system, and to improve energy efficiency, we need to model the energy consumption as a nonlinear function, which is about antenna selection power allocation. Then based on fractional programming theory, the paper proposes joint selection algorithm, namely, considering joint antenna selection and power allocation scheme. And all of these are verified by software. The simulation results show that when compared to the equal power allocation scheme, exhaustive search method and other algorithms, the optimal power allocation algorithm and the union algorithm proposed can significantly improve system efficiency and reduce energy consumption among algorithms. Finally, the paper summarizes all the prospects and elaborates plans for further study of the issue.