Key Generation for Secure Distributed Detection in IoT using Polar Quantization

The problem of securing the communication in an IoT sensor network from malicious eavesdroppers is studied. One-time pad encryption is found to be a suitable encryption method for this type of setting, reducing the problem to the generation of secret keys to be used for the encryption. We propose a novel physical-layer security based key generation protocol where a Gaussian source derived from the wireless communicaton channel between key generating pairs is transformed into an erasure channel. The proposed method is shown to outperform other similar methods when allowing for a higher BER in the generated keys and constraining the rate of communication. We also analyze how the BER of the generated keys affects the underlying inference task of the sensor network.