Implementation of a Free Space Laser Communicator

Any free space laser communicator has to face the issue of attenuation over an air channel as the distance gets larger. By using FSK (frequency shift keying) we can improve that situation. FSK modulation scheme is inherently more resistant to noise than OOK (On Off Keying) which is currently used in optical communication. By implementing FSK in an optical communication system we can get more range than the solutions currently available in the market. In this paper we show how we built an BFSK modulated free space laser-based data transmitter and receiver using cheap readily available components.