Towards Secure Over-The-Air Computation

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. It works for a large class of analog OTA computation schemes and we give two examples for such schemes that are contained in this class. The key ingredients in proving the security guarantees are a known result on channel resolvability and a generalization of existing results on coding for compound channels