urn:nasa:pds:context:instrument:dart.hga 1.0 1.21.0.0 Product_Context 2023-12-08 1.0 Created by PDS-SBN T.F. Barnes using information provided by the Dart mission. urn:nasa:pds:context:instrument_host:spacecraft.dart instrument_to_instrument_host 10.1109/IEEECONF35879.2020.9330400 M. Bray, "A Spiral Radial Line Slot Array Antenna for NASA's Double Asteroid Redirection Test (DART)," 2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting, Montreal, QC, Canada, 2020, pp. 379-380, doi: 10.1109/IEEECONF35879.2020.9330400. Instrument paper. DART High Gain Antenna (HGA) Radio Science 135003 The DART HGA is a Spiral Radial Line Slot Array that is gimballed. It is the primary antenna of DART that provides the RS data collected during the last 30 days of the mission. This low-cost, high-gain antenna enabled high-efficiency communications in a compact, planar form. DART operates at the X-band DSN frequencies of 7.168 (Uplink) and 8.422 GHz (Downlink). There is approximately a 15% difference in frequency between uplink and downlink (see Bray (2020)). The transponder delay (including RF propagation through waveguides, coax, etc.) is about 12650 nsec.