A correlation-based approach to detecting wireless physical covert channels

Abstract

With the rapid development of wireless communication technology, the openness of wireless communication makes it more likely to be threated by radio interception or even maliciously use. As a widely used way to exfiltrate information, the wireless covert channel brings a great threat to communication security. Compared with the wireless covert channel on the upper layer, the wireless covert channel based on the physical layer (WCC-P) has better concealment and greater capacity. However, due to the high variation in the wireless communication channel, detecting WCC-P is a challenging task. Existing detection schemes are ineffective at detecting most of WCC-P schemes. In this paper, we propose a new correlation-based scheme to detect WCC-P communication signal. The proposed detection scheme is based on the correlation coefficient of the constellation error vectors (CEV) for multiple antennas. The difference in the correlation coefficient of a detection process provides a critical clue for WCC-P signal detection. Exploiting this observation, we investigate the use of the correlation coefficient in detecting WCC-P communication signal. Simulations show that the proposed scheme can effectively detect WCC-P signal. When the signal-to-noise ratio (SNR) reaches 5 dB, the detection accuracy can reach more than 90%.