Cascaded Offset Optical Modulator

A unique challenge in the development of a deep space optical software-defined radio (SDR) transmitter is the optimization of the extinction ratio (ER). For a Mars to Earth optical link, an ER of greater than 33 dB may be necessary. A high ER, however, can be difficult to achieve at the low Pulse Position Modulation (PPM) orders and narrow slot widths required for high data rates.