Optical fiber audio and video communication system using AOM and LED

This paper describes the construction and performance of the single-mode (SM) optical fiber communication system utilizing the acousto-optic modulator (AOM) technique for modulation of audio and video signals. An edge-emitting LED (ELED) at an optical wavelength of 1300 nm was used as a light source. The output frequency response for the direct (Oth) and diffracted (1st) beams from the AOM used together with the ELED were flat over the frequency range of 50 Hz to 6 MHz. The differential gain (DG) and differential phase (DP) of the video signal were less than 5%, and 5 degrees, respectively, and the signal-to-noise ratio (SNR) was approximately 56 dB.