The clustering of satellites in cooperative fly formation constellations produces a lightweight, low cost, highly reliable and supraperformance space system. One way to communicate between the satellites is by a laser beam with a narrow divergence angle. To maintain line of sight between the transmitter and the receiver during the communication time, a steering device has to be incorporated into the communication system. We adopt a 2-D optical phased array (OPA) antenna. An OPA antenna is an attractive option for a steering device as it is lightweight, compact, and provides agile and inertia-free 2-D beam steering. We integrate two fields of study—OPA and laser communication theory—to attain a new perspective on communication system design. We theoretically analyze and model a laser intersatellite link using a 2-D OPA antenna and illustrate the model by a numerical simulation. The microsatellite antenna gain distribution statistics are derived from the OPA theory using the Monte Carlo method. We apply the results to evaluate system performance, particularly the effect of OPA phase errors. © 2003 Society of Photo-Optical Instrumentation Engineers.