MIMO信道空时联合功率优化

Spatial-Temporal Power Optimization for MIMO Channels

文章给出了评价MIMO信道质量的空域和时域准则,分别以MIMO系统各态历经容量最大化和中断容量最大化为目标,提出了空时联合的功率优化算法。对于各态历经容量最大化,采用空域和时域联合注水;对于中断容量最大化,在空域采用注水,时域上根据信道质量,仅分配满足一定中断概率要求的发射功率。仿真结果表明,空时联合优化与传统的空域注水得到的各态历经容量几乎相同,但是,引入时域自适应能够显著改善系统的中断特性。

This paper gives the criterion of MIMO channel quality in spatial and temporal domain, and proposes spatial-temporal power allocation strategy to achieve the maximal ergodic capacity and outage capacity, respectively. For the ergodic capacity, the optimal strategy is spatial-temporal waterfilling. While the optimal scheme for outage capacity is waterfilling in spatial domain ,whereas in time domain only the power satisfying certain outage probability in accordance with the channel quality is allocated. Simulation results show that the temporal power adaptation gives almost the same ergodic capacity as that of spatial-temporal waterfilling, and greatly enhances the outage performance.