Deployment verification of large CFRP helical high-gain antenna for AIS signals

Abstract

In this paper the development of the structural design of a deployable helical antenna made from fiber composite material as well as its deployment verification in Zero-G environment will presented 1,2. In the introduction the advantages of helical antennas will be pointed out and a potential field of application, the receiving of AIS (Automatic Identification System) signals from maritime vessels, will be presented. The next chapter deals with the antenna design where especially manufacturing aspects will be addressed. The test setup for deployment tests in weightlessness will be explained and the results recorded during the 15 th parabolic flight campaign (PFC) of DLR (German Aerospace Center) in March 2010 will be shown. During this campaign the deployment of 4 different helix antennas was tested as well as reaction forces and the dynamical behavior were recorded. An outlook is given on the subsequent finite element (FE) nonlinear numerical analysis. The aim of these calculations is to correlate analysis and test results, to use the correlated models for further improvements of antenna parameters, and to enhance predictions of the antenna behavior and its effect on the satellites attitude control during and after deployment.-TABLE OF CONTENTS 1. INTRODUCTION .

Software-defined radio with flexible RF front end for satellite maritime radio applications

“…One solution to this issue could be to reduce the beam width of the antenna, and thereby to decrease the coverage area. This case has already been analyzed and tested by DLR Bremen and demonstrated on the DLR satellite AISat [9]. The high gain helical antenna, used on AISat, cannot achieve a smaller coverage than 200 nautical miles.…”

Deployable Bistable Composite Helical Antennas for Small Satellite Applications

“…There are many stowage and deployment methods being investigated such as scrunch-up, roll-up, origami-folded, and actively controlled deployment mechanisms. AISat featured a 57 cm diameter, 4 m long helical antenna that deployed like a spring and was designed to receive AIS signals at 162 MHz [3,4]. Inherently small helical antennas (i.e.…”

“…The significant engineering challenge in achieving a small-satellite deployable solution is apparent from these calculations (1)- (3). The deployed helix has a diameter of approximately 60 cm and a height of 3.2 m whereas a '1U' CubeSat volume is only 10 cm x 10 cm x 10 cm.…”

“…exactView-9 [22]) do not require additional stiffening. Others have tried to address this by incorporating axial stiffeners [3,4] and a webs of composite strips [11]. Another approach deploys a compressed helically curved composite spring that is axially tensioned using polyimide tapes, to address the effects of creep on the deployed dimension, which arise in the stowed state [23].…”

“…In August 2014, AISat demonstrated the first in-space use of an axial mode (i.e. directional) helical antenna to detect AIS signals from ships [3,4]. The satellite operated at an altitude of 660 km and used a narrow beam targeted at a much smaller area just 750 km in diameter.…”