Design Of Indoor Distributed Antenna System And Research On Optimization Algorithms

The rapid increase in user demand for data rates in indoor scenarios has brought unprecedented challenges to designers of next-generation mobile communication systems.In order to provide a high-rate,high-efficiency,high-reliability indoor mobile communication network,many innovative solutions have emerged in the industry.Distributed antenna system,as an important candidate technology for 5G communication,has attracted great attention because of its advantages such as flexible deployment,low energy consumption,high channel capacity and few signal blind spots.The previous research on distributed antenna system mainly focused on outdoor scenarios with coverage of several kilometers.This paper focuses on the design and performance optimization of distributed antenna systems in indoor scenarios.Firstly,this paper summarizes the research background and significance of indoor mobile communication,and introduces the characteristics of wireless channels,including large-scale fading and small-scale fading.Then comprehensively consider various performance parameters of indoor signal propagation,and conduct three-dimensional modeling of indoor wireless channels.At the same time,the system architecture and downlink channel capacity of the distributed antenna system are analyzed.The effect of the antenna placement method,the number of antennas and the room area on the channel capacity has been verified.Several channel capacity optimization methods such as antenna selection and precoding technology are introduced.Afterwards it performed performance simulations for some typical optimization algorithms on channel capacity.Secondly,this paper introduces commonly used energy efficiency evaluation indicators,and builds an energy efficiency optimization model for indoor distributed antenna system deployment scenarios.In order to solve this problem,it is transformed into a two-step optimization solution process through mathematical methods.Solve the optimal number of antennas first,and then take the optimal number of antennas back to solve the relationship between the optimal energy efficiency and the user rate.Afterwards the relationship between the number of RRU,the number of antennas and the system energy efficiency in an actual scenario is simulated.Finally,the system architecture of C-RAN is introduced in detail,and the problem of limited fronthaul capacity constraint existing in C-RAN is analyzed.Combined with the cost problem of the wireless access network construction,an optimization model for the deployment cost of indoor distributed antenna systems was constructed.Based on this model,a single type RRU placement method and a hybrid RRU placement method were proposed.The proposed method was verified by performance simulation and analysis.Compared with the existing RRU placement method,the deployment cost of the indoor distributed antenna system can be greatly reduced.