Feasibility Study of Inflatable Antennas as Observational Antenna for Ultra Low Frequency CubeSat Applications

This paper presents a feasibility study on the use of an inflatable structure as observational antenna payload for a CubeSat. The objective for the antenna is to detect signals originating from the Dark Ages, which are expected to be between 80 kHz and 30 MHz. For this, antennas are needed with a large effective aperture to increase the sensitivity as well as to be sensitive to the low frequency signals, and which still fit inside a CubeSat. One of the ways to deploy a large structure which is packed in a small volume during launch, is by using inflatable antennas. Previous work has shown the feasibility of using inflatable antennas as reflector antennas. The novelty in this work is the study on the use of the inflatable antenna as an observational antenna instead of a directive reflector antenna. Here the radiating active antenna elements are printed on the thin membrane. An analysis is done on usable antenna designs that can be used for the application and specifically for these inflatable structures. Next an analysis on the possible practical implementation of such a system is done including but not limited to the material the membrane, method of inflation and folding techniques. In the end, a possible design is shown, which uses 8 sinuous antennas on very thin PVE film with a conductive coating. A scale model using generic cost-effective PCB material is shown which will be further investigated and tested. Future research will demonstrate an actual practical test.