高空平台通信系统中多波束天线辐射特性对系统性能的影响

高空平台通信系统中将采用多波束天线提供蜂窝覆盖，来提高系统容量。本文分析等波束宽度和等波束面积两种类型多波束天线辐射特性以及它们的几何模型，推导了载干比计算公式，通过仿真分析不同参数配置条件下多波束天线辐射特性对系统载干比性能的影响。研究表明等波束面积多波束天线比等波束宽度多波束天线具有更好的载干比分布特性。本文得出的结论对HAP通信系统规划具有重要的指导意义。

Effect of Mulit- Beam Antenna Radiation Characteristics on System Performance in HAPS

In the HAP （High Altitude Platform） based communications system, multi -beam antenna is adopted to provide the cellular coverage and to improve the system performance. This paper analysizes the radiation characteristic and the geometrical model for two types of multi - beam antennas, namely the equal beamwidth multi - beam and the equal beam coverage area multi - beam. The CIR（ Carrier to Interference Ratio） formula has been deduced. We analyse the effect of the mulit - beam antenna radiation characteristic on the system CIR performance for different configurations through simulation. Research results show that the equal coverage area mulit - beam has better CIR distribution characteristics compared with the equal beamwidth mulit -beam antenna. The conclusion educed in this paper is of great meaning to the planning of the HAP based communications system.