高空平台-地面CDMA系统上行容量提高

Method for improving the uplink capacity of an integrated high altitude platform station-terrestrial CDMA system

根据高空平台CDMA系统的邻小区干扰因子小于地面CDMA系统的特点,分析了现有环状小区分布结构存在的问题,提出一种多层小区分布结构,即相邻层的地面小区间间隔着若干层高空平台小区.推导出了高空平台-地面CDMA同频系统上行链路容量的表达式,比较了环状小区结构和多层小区结构下系统上行链路容量的大小.仿真表明,小区总层数为10时,环状结构下高空平台上行链路容量和地面上行链路容量分别为97.4和97.6,多层结构下高空平台上行链路容量和地面上行链路容量增加至111.9和110.2.

According to the characteristic that the inter-cell interference factor of the HAPS CDMA system is lower than that of the terrestrial CDMA system, the disadvantage of the ring structure is pointed out and an improved multi-layer structure is proposed in which two adjacent terrestrial layers are seperated by several HAPS layers. The uplink capacity formula for the HAPS-terrestrial CDMA system is deduced and the capacity of the ring structure and that of the multi-layer structure are compared. Numerical results show that the uplink capacity of the HAPS system and that of the terrestrial system of the multi-layer structure increase to 111.9 and 110.2 respectively for a 10-tier system, while the uplink capacity of HAPS system and that of the terrestrial system of the ring structure are only 97.4 and 97.6 under the same condition.