采用L條支路最大比合并分集接收的相關瑞利衰落信道容量，推導恒定發射功率自適應M進制正交幅度調制的頻譜效率，并將它們與獨立同分布瑞利衰落信道理論容量進行比較。數值結果闡明相關性和天線設置對瑞利衰落信道容量和自適應M進制正交幅度調制性能的影響。

Closed-form solutions for the correlated Rayleigh fading channel capacity under L-branch Maximum Ratio Combining (MRC) diversity reception are obtained in this paper. The performance of constant-power adaptive M-ary Quadrature Amplitude Modulation (MQAM) schemes over correlated Rayleigh channels under MRC diversity reception is investigated. Closed-form expressions for spectral efficiency of adaptive MQAM assuming perfect channel estimation and negligible time delay are derived. Numerical results that illustrate the effect of correlation and antenna configurations on the correlated Rayleigh fading capacity and spectral efficiency of adaptive MQAM are also presented