非完美信道估计条件下多比特量化无线密钥生成性能分析

针对无线密钥生成过程中的信道估计误差导致信道测量参数互易性差，严重影响通信双方生成密钥一致性的问题，提出了非完美信道估计条件下多比特量化无线密钥生成方案。首先，建立信道估计误差模型，研究非完美信道估计对无线密钥生成的影响，然后设计添加保护带的多比特密钥量化器，通过优化量化参数改善无线密钥性能。推导得到了密钥不一致率（KDR）和有效密钥速率（EKGR）的闭式表达结果，并揭示了导频信号功率、量化阶数和保护带与以上两个密钥性能指标的关系。仿真结果表明：增大发送导频功率可以有效降低密钥不一致率，提高量化阶数可以提升密钥生成速率但KDR也随之升高，增大量化阶数同时选择合适的保护带大小可以有效降低KDR。

Performance analysis of wireless key generation with multi-bit quantization under imperfect channel estimation condition

The channel estimation error seriously affects the key generation consistency of two communicating parties in the process of wireless key generation, a multi-bit quantization wireless key generation scheme under imperfect channel estimation condition was proposed. Firstly, in order to investigate the influence of imperfect channel estimation on wireless key generation, a channel estimation error model was established. Then, a multi-bit key quantizer with guard band was designed, and the performance of wireless key was able to be improved by optimizing the quantization parameters. The closed-form expressions of Key Disagreement Rate (KDR) and Effective Key Generation Rate (EKGR) were derived, and the relationships between pilot signal power, quantization order, guard bands and the above two key generation performance indicators were revealed. The simulation results show that, increasing the transmit pilot power can effectively reduce the KDR, and with the increasing of quantization order, the key generation rate can be improved, but the KDR also increases. Moreover, increasing the quantization order and choosing the appropriate guard band size at the same time can effectively reduce KDR.