Ultra-wide bandwidth laser communications: Part I—System considerations for a satellite link

A design concept for an optical data relay link between two earth satellites is presented for missions requiring ultra-wide information bandwidths, 100 to 1000 MHz, and detected signal-to-noise ratios greater than 30 dB. Only analog modulation is considered owing to the inherent complexity in digitizing analog data of the bandwidths of interest. The optical system is compared to a microwave system on the basis of the primary power required at the transmitter, using system and component characteristics likely to be achieved with a moderate development effort. The conclusion is that an optical system will require an order-of-magnitude less power than the best microwave system.