Design of transmitter communication module for nanosatellite optical communication terminal

In the present world of satellites, miniaturization of satellite subsystems plays a vital role in launch capacity and operational maintenance. Free-space optical communications with lasers offer an attractive alternative to traditional radio frequency (RF) communications and enable a reduction in size, weight, and power (SWaP). In this work, we have studied and designed the transmitter module for nanosatellite-optical communication terminal (NOCT) to provide power-efficient and high data rate downlink using infrared lasers from low earth orbit satellites. In this paper, we present the requirements for the functional design of the transmitter system. We design an optical link for low-earth orbit (LEO) satellites and evaluate the relation between the bit error rate (BER) and receiver sensitivity for the pulse position modulation (PPM) systems. We also characterize the Erbium-doped fiber amplifier (EDFA) for validation of design using the free-space optical link.