Security-Aware Waveform and Artificial Noise Design for Time-Reversal-Based Transmission

Among the plenty of studies on physical layer security, multi-antenna signal processing and nodes cooperation are two widely adopted techniques. However, in practical systems there are many single-antenna devices that do not support cooperative transmission either. To guarantee the information security in this scenario, we propose a novel transmission strategy that exploits the temporal characteristics of a multipath fading channel. Specifically, we apply this strategy to a time-reversal-based communication system. We consider a joint design of signal waveform and artificial noise. Based on this approach, specific transmission schemes are designed for the cases with and without eavesdropper's channel state information (CSI), respectively. The numerical results show the superiority of our proposed schemes in terms of security enhancement even when the eavesdropper's CSI is unavailable.