A hybrid channel estimation strategy against pilot spoofing attack in MISO system

Abstract

Pilot spoofing attack can deteriorate the transmission performance of the legitimate system and facilitate eavesdropping concurrently. Some detection methods of pilot attack have been proposed, while we consider the problem of channel estimation under pilot spoofing attack. In this paper, a hybrid channel estimation strategy using random Binary Phase Shift Keying (BPSK) is proposed. Specifically, a random BPSK sequence is transmitted by the legal user once the attack is detected. In this manner, the base station detects the sequence and re-estimates the legal channel with both contaminated pilot and assistant sequence. We evaluate the estimation performance in three cases according to different responses of the malicious user. Simulation results demonstrate that the proposed strategy can effectively estimate the legitimate channel against pilot attack.