A distributed multi-antenna space hopping transceiver technique in backward training mode

Since 0/1 space hopping technique in forward training mode has security problems after the leak of space hopping pattern, a backward training technique with weight-feedback is proposed. Through backward training between transmitter and target user, the target user can obtain weights that are equivalent with those generated from forward training, while eavesdropper, even if she steals the space hopping pattern, cannot correctly demodulate, because of the diversity of wireless channels. It is this technique that is completely different from traditional frequency hopping spread spectrum technique. The proposed technique aims at fundamentally solving the security problem of wireless communications, makes full use of abundant space-time spectrum resources of wireless signals and ensures secure transmission in physical layer. 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.