Deployable Antennas for Small Satellite Constellation Missions

The Space Flight Laboratory (SFL) and HawkEye 360 have optimized the radio frequency (RF) design end the corresponding geometric requirements for the mechanical design of a deployable discone antenna. This high-performance deployable discone antenna maximizes its utility per volume of the small satellite for which it has been designed and built.\nDeployables on small satellite constellation missions should be low-cost, manufacturable, and high-performance. This means that deployables must be capable of repeated stowage performed during test deployments without hindering performance or flight qualification. This deployable antenna will be launched and commissioned April 2024, making it the first ever on-orbit wideband deployable discone antenna to gain flight heritage.\nThe rise of constellation missions in recent years has been enabled by the ever-increasing accessibility to space technology. More specifically, through the employment of small, low-cost, yet high-performance small satellites, constellation missions allow for space technology to have an exponentially larger impact than a single spacecraft through increased coverage and reduced revisit intervals. The data collected form constellation missions contributes to global monitoring and surveillance, security and defense, environmental monitoring, and communication and connectivity. HawkEye 360 employs a constellation of satellites to deliver commercially available precision mapping of radio frequency emissions. This unique ability to identify and geolocate sources of radio frequencies from space reveals previously invisible knowledge about activities around the world.\nThe range of possible components on small satellites is limited by spacecraft surface area and volume, especcially so with respect to antennas. Antennas require specific geometry, volume, and surface area in order to meet performance requirements. One solution to these limitations of smaller satellites is to incorporate the use of deployable mechanisms. In the context of antennas, deployables allow for a much wider range of possibilities in terms of RF performance and coverage which can be flown on a smaller spacecraft. Small satellites work with a large number of design constraints that can make the addition of wideband RF coverage a mechanical challenge. Small satellites equipped with a deployable wideband antenna like the discone antenna have the capability to substantially expand RF coverage of low-cost constellation missions.\nThis paper will describe SFL's role in the building of a microsat-compatible deployable discone antenna as well as the observations made on-orbit when it gains flight heritage in April 2024. Moreover, it will discuss SFL and HawkEye 360's vital contributions to RF constellation missions, the launch of the first spacecraft to have discone antennas, and the on-orbit deployment behaviour of this new innovation built and integrated by SFL.