2018.B.4.1. The Development of a Novel, Cost Effective Tri-Filar Deployable VHF Antenna for MicroSatellite Applications

Author(s)

Juan Reveles (1)
Mat Rowe (1)
Tao Huang (1)
Vincet Fraux (1)
Mike Lawton (1)

Oxford Space Systems, United Kingdom

Session

B.4

Keywords

Deployable, tri-filar antenna, microsatellite, stowage efficiency

Abstract

In the context of unfurlable space structures, an ongoing challenge is to maximise the stowage efficiency of large deployable structures, as volume available for payloads onboard launchers is highly limited and payload mass incurs a high cost penalty – around £20,000 per kilogram to reach orbit. In this paper, a high stowage efficiency, helical trifilar antenna for VHF telecommunications is profiled. The deployable antenna uses origami folding techniques, a passive stored-energy deployment system and a tensegrity tensioning structure. The antenna is designed to provide very high stowage efficiency, with the ability to stow from a deployed length of 2.7 m to a height of 0.10m and a store diameter of 0.25m.

The helical antenna is shaped using a prismatic compliant structure, maintained by triangular support trusses, while stored-energy copper-beryllium conductors form a triple helix which impart the required radiofrequency capability. The shaping surface, inspired by kite design, provides additional structural integrity to the antenna and possesses an exposed area large enough to act as passive thermal control if required. The folding pattern allows the antenna to be stored in a small volume, details of the folding pattern will be set out in the full paper.

Due to its high stowage efficiency the antenna is compatible with large satellite and microsat platforms, it is intended for dual downlink and uplink in the VHF band, with a maximum gain of 6dBi. A demonstrator has been developed which proves the kinematic properties of the proposed antenna architecture and its compatibility with the NewSpace development philosophy. In the full paper, more detail is given on radiofrequency performance, as well as its structural, thermal, and functional capabilities with specific focus on designing such motion structures for the demanding and unique environment of space.