分析了分布式大规模多输入多输出（multiple-input multiple-output，MIMO）系统在射频（radio frequency，RF）链路失配情况下的性能，基于性能分析和最大比传输（maxratio transmission，MRT）原理，推导了系统下行链路可达速率的闭式表达式.仿真结果表明，该表达式可有效评估基站端（base station，BS）射频失配情况下的系统性能.基站端超过1 dB的幅度失配或π/2的相位失配，都将导致用户端有超过50%的下行速率损失.射频失配对系统性能的影响十分严重，也说明了对射频失配进行性能分析的必要性.
The performance analysis of the distributed massive multiple-input multipleoutput (MIMO) system under the mismatch of the radio frequency (RF) circuits is studied. Based on the performance analysis and the principle of max ratio transmission (MRT), a closed-form expression of achievable downlink rate is derived. The result of simulation validates that the RF mismatch on base station (BS) can be well evaluated with this expression. If the amplitude variance of RF gain is more than 1 dB or the phase of RF mismatch is more than π/2 on BS, the maximum of the achievable downlink rate loss of users is ffty percent larger than a system with ideal RF. The system performance is seriously affected by the RF mismatch, which verifes that the performance analysis for the RF mismatch is indispensable.
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