Self-interference cancellation for cooperative jamming communications with nonideal alignment and channel equalization

For the security of wireless communications, cooperative jamming can be used to intentionally degrade the signal-to-noise ratios received by eavesdroppers. Unfortunately, this jamming may also propagate to the legal receiver and then becomes a harmful self-interference (SI), which should be cancelled for reliable detection of the desired signal. In this paper, by comprehensively considering nonideal time-frequency alignment and channel equalization, SI-cancellation capability is investigated for the additive white Gaussian noise channel. Theoretical and simulation results demonstrated that the impact of the frequency alignment error is more serious than that of the time alignment and channel equalization errors. Moreover, it is illustrated that weaker SI power can tolerate a larger range of those nonidealities.