Inflatable Antenna

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Clik here to view.© Niels Vertegaal

On Wednesday 6 December, an high altitude balloon experiment was performed for an inflatable antenna in space. It was launched at 11:00 in Wales and landed safely at 13:30 on the East side of the UK. The goal of the experiment was to present and demonstrate the feasibility of using an inflatable antenna for space applications. With the final goal of the project being related to the measurements the signals originating from the Dark Ages at ultra-low frequencies. To achieve this, large and sensitive antennas are need in the form of a constellation, or as radio telescope on the far side of the moon. As during a launch every gram and volume counts, an efficient method of achieving these antennas is the use of an inflatable structure.

The inflatable antenna consisted of four antennas operating at 2.4 GHz (allowing for comparable measurements on Earth). The high altitude balloon brought the experiment to an altitude of 32 km, before being cut away to make sure that the antenna does not fall in the sea. During the deployment one of the inflatable arms got stuck, unfortunately, which meant that full deployment was delayed until the physical shock from disconnect the high altitude balloon release the arm. Therefor, only a small period of time was available for measurements.

At the moment, the results are being processed. However, some of the results already show that the antenna operated as intended at the time of full deployment. On the image you can see the following: The camera is attached to the experiment thermal box (in black), which has a red box attached of 10x10x10cm, which contained the antenna during launch. Thanks to ASTRON, the inflatable structure of the 1m^2 antenna was built using 25um Kapton, in combination with 2um copper for the antennas. The white circle is the high altitude balloon.

Although there are still many challenges to overcome to go from an university experiment to a long term reliable product with an high TRL level, the first step has been made.