We propose a new method to protect Over-The-Air (OTA) computation schemes against passive eavesdropping. Our method uses a friendly jammer whose signal is -- contrary to common intuition -- stronger at the legitimate receiver than it is at the eavesdropper. We focus on the computation of arithmetic averages over an OTA channel. The derived secrecy guarantee translates to a lower bound on the eavesdropper's mean square error while the question of how to provide operationally more significant guarantees such as semantic security remains open for future work. The key ingredients in proving the security guarantees are a known result on channel resolvability and a generalization of existing achievability results on coding for compound channels.

翻译：我们提出了一种新方法，用于保护空中计算方案免受被动窃听。该方法利用友好干扰器，其信号——与常规直觉相反——在合法接收机处比在窃听者处更强。我们聚焦于通过空中信道计算算术平均值。推导出的保密保证转化为窃听者均方误差的下界，而如何提供语义安全等操作上更有意义的保证仍有待未来研究。证明安全保证的关键要素包括信道可分辨性的已知结论以及对复合信道编码现有可达性结果的推广。