Dynamic communication system characterization of phased array antennas

Phased array antenna (PAA) systems offer many advantages when used on a low Earth orbiting (LEO) satellite system. Technology advancements to reduce the power, weight, and cost of these systems make phased arrays a competitive alternative compared to the gimbled reflector system commonly used in science missions. However, the operational characteristics of LEO communications links that employ a PAA are not fully understood. For example, theoretical and computer simulation analysis of a phased array antenna operating in a communication link predict 3-4 dB of degradation of BER performance for high rate systems. The degrading effect of large scan angles on high data rate communications is being investigated in a laboratory environment. In these experiments a LEO environment is simulated by dynamically scanning the array while simultaneously rotating the range pedestal in the complimentary direction. Such investigation reduces the operational risk of deploying high frequency PAA technology. This characterization bounds the degradation associated with operating the phased array systems in this environment, and provides for the opportunity to system engineer the communication link.