星地一体化通信系统地面网络可用带宽分析

Analysis of terrestrial network's available spectrum in integrated satellite and terrestrial mobile systems

星地一体化通信系统,是由基于多波束的卫星网络与地面辅助网络组成,它们共用一段频率。辅助地面网络的目的在于提高卫星波束在高密度人口区域的覆盖性能,这些区域中,卫星通信由于高楼而受到信号阴影衰减。地面网络的可用带宽随着禁区域卫星频率复用改变而改变,为了更加准确分析地面网络可用带宽的多少,在假定某区域人口密度均匀分布的条件下,提出了禁区的概念与一种新的全概率计算方法,并利用该方法分析卫星波束频率复用因子与禁区大小对地面辅助网络可用带宽的影响。

The term ＂integrated system＂ refers to a system composed of a multibeam satellite based network and a ancillary terrestrial network that reuses the same frequency band than satellite＇s ones.The terrestrial component aims at improving the satellite coverage in highly populated areas where satellite communications often suffer form a high blocking factor caused by the buildings.The available terrestrial spectrum changes according to different exclusion zone and the satellite frequency reuse pattern,in order to analyze more accurately available spectrum of terrestrial network under the condition of uniform distribution of population density,exclusion zone is defined and a new calculating method is obtained by total probability theorem.The influence of several parameters such as the satellite frequency reuse pattern and the exclusion zone size between terrestrial and satellite cells is ptesented by the method.