Abstract
We propose an optical transmission system for realizing TV live broadcast from a midget submarine in the deep sea. At first, the system transmits video signal from the submarine to a repeater through water using blue LEDs, then transmits it to a ship on the sea through an optical fiber. Tracking technology for optical beam is important, because the submarine and the repeater moves about. We devised a new method for detecting misalignment of optical beam easily by covering the surface of the repeater with retro-reflective sheet. We made a fundamental indoor experiment for examining feasibility of proposed system. Received optical power obtained at the experiment agreed with theory. More, we succeeded in improving CN ratio by combining FM signals obtained at plural optical receivers.
