Self-Noise Based Physical-Layer Secure Communication: Transceiver Design and Performance Analysis

In single-input single-output (SISO) systems, transmitting the expected signals with artificially generated noise can effectively enhance the physical layer security (PLS). However, the traditional noise suppression at the intended receivers will increase algorithm complexity, particularly over multi-path fading channels, which poses challenges for some massive Internet-of-Things (IoT) networks that take advantage of low-cost and resource-constrained nodes. In this paper, we design a novel self-noise (SN) waveform for transmission security. The transmitter stacks the signal segments periodically, and the additive SN in the current signal period derives from the previous signal periods. Based on this, SN can be completely suppressed at intended receivers by differential operations between two adjacent signal periods. Both analysis and simulation results confirm that the proposed scheme can significantly reduce the complexity of noise suppression and its performance is not affected by multi-path channel environments. Besides, the proposed scheme can effectively worsen the signal-to-noise ratio (SNR) of eavesdroppers while having negligible impacts on intended receivers.