为了能够对多用户条件下分布式和集中式天线系统所支持的用户分布密度和服务质量进行定量地比较,提出了一种基于随机几何的性能分析方法.当用户在小区内服从泊松分布时,这种方法可以得到精确的分布式与集中式天线系统的传输容量表达式.从分布式天线系统的传输容量表达式可以发现,在给定用户分布密度时,为了满足一定的服务质量要求,用户的接入距离存在一个上限.分析和仿真结果表明,在相同条件下,与集中式天线系统相比,分布式天线系统能够容纳更多的用户和支持更高的服务质量要求.
In order to quantificationally compare the supported user distribution density and quality of service (QoS) by distributed antenna system (DAS) and co located antenna system (CAS) under multiuser condition, a stochastic geometry based performance analysis method is proposed. When the users have a Poisson distribution in the cell, this method can obtain the exact expression of transmission capacity for the two multi-antenna systems. From the expression of transmission capacity for DAS, it is found that, given the user distribution density, in order to satisfy a certain QoS requirement, there is an upper bound of user access distance. Both theoretical analysis and simulation results show that, under the same condition, compared with CAS, DAS is able to admit more users and support higher QoS.