Development of optical wireless transceiver for data communication in small satellites

Design technique for optical wireless transceiver is discussed for modular Nano-satellites using low cost COTS components. The proposed transceiver structure uses Infrared Light Emitting Diode to transmit pulses in the near infrared spectrum. The receiver circuit consists of photodiode, preamplifier, post amplifier and a comparator stage. Since noise is a major problem for receiver, a very low noise preamplifier and post amplifier stages have been selected. Since the communication system is inside the satellite, there is possibility of sunlight to enter from small holes and blind the receiver. This problem is solved by attenuation circuit. Displacement damage effect on selected LEDs and photodiodes has been calculated and the resulting drop in efficiency has been verified using proposed transceiver. This optical wireless module is fully scalable depending on the needs of the system and can coexist with more traditional wired communication channels as required.