Uplink Arraying for Solar System Radar and Radio Science

To improve the uplink capability of the Deep Space Network at X-band frequencies near 7.2 GHz and to potentially prepare for retirement of the aging 70-m antennas, the National Aeronautics and Space Administration (NASA) has sponsored two experimental campaigns at the Jet Propulsion Laboratory (JPL, Pasadena, CA) and one at Harris Corporation (Palm Bay, FL) to show the feasibility of uplink arraying for deep space communication. These three efforts made significant progress in demonstrating the uplink arraying concept and in advancing our understanding of the associated error budget. These efforts focused primarily on demonstrating the feasibility of uplink arraying for communications applications. Uplink arraying is also useful for applications other than routine communications, mainly solar system radar and radio science. Among topics investigated are features and characteristics such as the array bandwidth, atmospheric calibration, array phase and amplitude stability, array blind pointing, and array delay calibration. No insurmountable obstacles are identified for the application of uplink arraying to noncommunications services. However, additional studies are recommended to minimize risk to radar and radio science services.