Optical Inter-Satellite Communication Operational
Optical inter-satellite communication based on TESAT Laser Communication Terminals (LCT's) is operational by now on LEO satellites for more than two years. The LCT's demonstrate their performance in LEO-LEO Inter-Satellite Links (ISL) and they are used also for LEO-to-ground links to investigate beam propagation through the atmosphere. Based on homodyne BPSK, a highly robust and sun light immune modulation scheme, the LCT's offer a full duplex data rate of 5.625 Gbps at a bit error rate lower than 10-9 for ISL. The LCT operations in the dynamic LEO scenario has shown that spatial and frequency acquisition can reliably be achieved within a few seconds. Due to its demonstrated performance, TESAT LCT's were selected for the European Data Relay Satellite (EDRS) Program of the European Space Agency.