Automated Synthesis of a Lunar Satellite Antenna System

In recent years, spacecraft requirements have trended toward smaller, lighter, and less expensive systems with more capabilities. At the same time, demands on the communication systems have increased, including faster data rates, lower power budgets, reduced system volume, and smaller link margins. The combination of these factors has posed numerous engineering challenges for antenna system designers, often forming complex tradeoffs among design parameters such as bandwidth, pattern control, beamwidth, and antenna size. In this paper, we show how a challenging set of antenna requirements were met for NASA's recent LADEE mission. We focus on the difficulties inherent in the requirements for both omnidirectional and medium gain antennas, both in S-band. We present techniques used to develop a requirements-compliant system based on our research in antenna synthesis methods. Compared to the conventional antennas considered by NASA for the mission, the antennas we developed yielded 65% increased downlink coverage and 44% cost savings for the mission. The deployed flight antennas were the only antennas on the mission and performed above expectations during the 8-month mission, which concluded in April 2014.