Single-Photon Lasercom Readout Integrated Circuit (ROIC)

To satisfy NASA?s deep-space communications needs, a 128 x 128-element readout integrated circuit (ROIC) will be developed for integration with Geiger-mode (Gm) avalanche photodiode (APD) detector arrays. The ROIC features integrated imaging, background subtraction, and time-resolved (sub-nanosecond) photon-counting functionality. The ROIC, when integrated with InGaAs Gm-APD arrays, will enable acquisition, tracking, and ranging of the 1064 nm ? 1570 nm optical radiation used in free-space optical links. This ROIC development will enable the manufacture of highly functional single-photon focal-plane arrays, offering the capability to reduce laser beacon power 100 times over analog optical detector arrays. In Phase II, the ROIC design will be completed, fabricated using a domestic CMOS process, and fully tested and characterized using a detector array. It will allow, in subsequent program phases, InGaAs Gm-APD focal-plane arrays to be fabricated.