ukfrosty

Hi all, I'm very new to electronics. I was reading some docs about the tracking of fish through the oceans. Radiowaves only seem to be feasible in shallow coastal waters. I was wondering how hard it would be to make a shallow water locator. One that would simply tell the receiver which direction the tracker was in. eg. by the signal getting stronger (not depth etc) when the antenna points in the right direction. Thanks for any ideas, ut's purely out of interrest ;)