Space Hopping Secure Transmissions in Backward Training with Weight-Feedback

• 1、School of Electronics and Information Engineering, Xi'an Jiaotong University, Xi'an 710049

Abstract：Since 0/1 space hopping technique in forward training mode has security problems after the leak of space hopping pattern, the backward training technique with weight-feedback is proposed. Through backward training between the transmitter and the target user, the target user can obtain the weights equivalent with that from forward training, while the eavesdropper cannot demodulate correctly because of the diversity of the wireless channel even if she steals the space hopping pattern, which is completely different from traditional frequency hopping spread spectrum technique. The proposed technique, which aims at solving the problem of secure wireless communications fundamentally, makes full use of the abundant space-time spectrum resources of the wireless signals and ensures the secure physical layer transmission. Simulation results show that even when both the space hopping pattern and the feedback weights are leaked，the eavesdropper keeps a high symbol error rate and cannot intercept information.

Keywords： wireless communication techniques physical layer security multi-antenna space hopping space-time spectrum