研究基于解码转发（DF）中继的三跳混合射频/自由空间光/射频（RF/FSO/RF）航空通信链路性能。航空子节点到骨干节点为RF链路，骨干节点之间为FSO链路，并假设三跳中的调制方式相同，RF信道服从Nakagami-m衰落模型，FSO信道服从Exponentiated Weibull大气湍流分布模型。推导了端到端中断概率（OP）和平均误码率（BER）的闭合表达式，分析了大气湍流强度、RF信道衰落系数及不同调制方式对系统OP、平均BER性能的影响。结果表明：在三跳DF中继方式下，最优的OP、BER性能取决于信道质量最差的一跳，二进制相移键控（BPSK）调制误码性能要优于二进制频移键控（BFSK）调制及高阶PSK调制。推导的闭合表达式有利于量化分析链路性能，为系统设计提供参考。

In this study， the performance of a three-hop hybrid radio frequency/free space optical/radio frequency （RF/FSO/RF） airborne communication link based on decode-and-forward （DF） relaying is investigated. The connection link between the airborne subnode and the backbone node is the RF link， whereas that between the airborne backbone node and the backbone node is the FSO link. The same modulation method is assumed in the three hops. The RF channel is characterized using the Nakagami-m fading model， and the FSO channel follows the Exponentiated Weibull atmospheric turbulence distribution model. Further， closed expressions are obtained for the end-to-end outage probability （OP） and the average bit error rate （BER）. Subsequently， the effects of turbulence intensities， RF channel fading coefficients， and modulation modes on the OP and average BER are analyzed. The obtained results indicate that in the three-hop DF relaying mode， the optimal OP and BER are dependent on the hop with the worst channel quality. Furthermore， binary phase shift keying （BPSK） modulation outperforms binary frequency shift keying （BFSK） modulation and high-order PSK with respect to the BER. The deduced closed expression is conducive for quantitatively analyzing the link performance and provides a reference for system design.