Wireless Covert Channel With Polarized Dirty Constellation in Backscatter Communication

Abstract Ambient backscatter communication has become a low-cost and green solution to next-generation Internet-of-Things (IoT). In this paper, we investigate a problem of wireless covert communication in backscatter communication system. The purpose of covert communication is to hide the process of communication and avoid being detected by eavesdropper. Covert messages are modulated into a random-like noise, and then superimposed on the carrier signal. Specially, we propose a wireless covert channel with polarization dirty constellation (WCC-PDC), which is polarized to solve the problem of low signal power in backscatter communication. Some methods are used to combine covert code block with carrier information block and increase the undetectability of covert communication. Additionally, successive-cancellation decoder and successive-cancellation list decoder are adopted to improve the reliability of WCC-PDC. Simulation results are finally provided to verify the improvement of undetectability and reliability with WCC-PDC.