Sub-band detection of primary user emulation attacks in OFDM-based cognitive radio networks

This paper considers the primary user emulation attack (PUEA) problem in OFDM-based cognitive radio networks, and proposes a robust and efficient AES-based digital TV (DTV) scheme. In the proposed scheme, the existing reference sequence used to generate the pilot subcarriers in the DTV frames is encrypted using the Advanced Encryption Standard (AES) algorithm for accurate sub-band detection of the authorized primary user, as well as malicious user. For primary user detection, we investigate the cross-correlation between the received sequence and the AES-encrypted reference sequence over a specific frequency sub-band. The malicious user detection can be performed by investigating the auto-correlation of the received sequence. We analyze the effectiveness of the proposed approach through both theoretical derivation and simulation examples. It is shown that, with the AES-based DTV scheme, both the primary user and malicious user can be detected accurately under primary user emulation attacks.