Multi-access communication system in a highly reverberant environment

We investigate by numerical EM simulation the potential communication channel capacity of a reverberant environment using the time reversal approach, excited at 2.4 GHz by ON-OFF keyed RF pulse excitation. It is shown that approximately 725 1.25MHz propagation channels can be allocated with the cavity contains a 4×4 λ or 1×1 λ LOS obstruction positioned between the transceiver antenna and the time reversal unit. Furthermore the results show that two co-located transceiver dipoles separated by a spacing of 3λ/4 can successfully resolve a 10ns pulse. Our findings suggest that different independent channels with identical operating frequency can be realized in an enclosed environment such as ventilation duct or underground tunnel. This suggests that there is a possibility of implementing a parallel channel radio link with the minimum inter-antenna spacing of 3λ/4 between the transceivers in a rich multipath environment.