Reference-frame-independent quantum key distribution (RFI-QKD) has been proved to be tolerant against unknown reference frame misalignment, which reserves interesting prospects in implementing global quantum communication. However, few works have been addressed on the performance and feasibility for RFI-QKD in turbulent atmospheric channels. Here, we propose to implement RFI-QKD in practical free-space links with fluctuating transmission efficiency due to beam wandering and broadening. An improved model for estimating the probability distribution of single-photon receiving efficiency has been developed and we also simulated the Gaussian beam spot evolution and secure key rate based on that. Results show that the beam wandering model of probability distribution of transmission efficiency is reasonable to improve the performance of RFI-QKD in free-space channel.

中文翻译：

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具有随机大气传输效率的与参考帧无关的量子密钥分配

与参考帧无关的量子密钥分发（RFI-QKD）已被证明可以容忍未知的参考帧错位，这为实现全球量子通信保留了有趣的前景。然而，关于 RFI-QKD 在湍流大气通道中的性能和可行性的研究很少。在这里，我们建议在实际的自由空间链路中实施 RFI-QKD，由于波束漂移和展宽，传输效率会波动。开发了一种估计单光子接收效率概率分布的改进模型，并在此基础上模拟了高斯束斑演化和安全密钥率。