Abstract: A method and apparatus for transmitting radio frequency signals and associated information through a plurality of compartments and associated bulkhead walls in a water vessel. The method and apparatus includes a through-the-bulkhead repeater system, in which one or more bi-directional repeater units are mounted on bulkhead walls in each compartment. The bi-directional units communicate with each other to transfer signals throughout the vessel. In operation, a bi-directional unit converts radio frequency signals into energy forms such as ultrasonic waves, which are propagated from one compartment to an adjacent compartment through the thick bulkhead walls. The propagated energy forms are received in the adjacent compartment by another bi-directional unit, which eventually converts the energy form into an output radio frequency signal, which is then transmitted by the bi-directional unit.