TEC-EEA Final Presentation Day - Recent Antenna and RF Material Developments

Wednesday 2 Dec 2015, 09:15 → 16:15 Europe/Amsterdam

Newton 1 (ESA/Estec)

Nelson Fonseca (European Space Agency)

You are cordially invited to attend the Final Presentation Day organized by the Antenna and Sub-Millimetre Wave Section on the subject of “Recent Antenna and RF materials Developments”. This Final Presentation Day will be held on the 2^nd of December 2015 at ESA/ESTEC, Noordwijk, The Netherlands (Newton 1 meeting room).

The full day programme starting at 9:15 is detailed in the 'timetable' section. Each presentation will last about 60 minutes, including questions. A brief summary for each activity and associated time slot can be downloaded by clicking on 'Programme' here below. Feel free to forward this invitation to colleagues that may be interested in these developments.

Please fill in the registration form to confirm your attendance and enable non-ESA attendees to access the site.

09:15 Introduction

1 Enhanced RF behaviour multi-layer thermal insulator (ITI, 50 k€)

The activity is dedicated to investigate the possibility of exploiting the modulated metasurface concept to control unwanted coupling, between antennas that are set on the same platform, due to the specular reflection associated to the high reflectivity of Multi-layer thermal insulation blankets.

2 Antenna architectures and technologies for reduced beamwidth multiple beam coverage (TRP, 300 k€)

Ka-band multimedia systems for Telecommunication mission offer larger frequency bands applications allowing higher data rates per user. A high system capacity implies a large number of beams to obtain an important reuse factor. One of the next challenging targets will be to provide a next generation of very compact feed able to comply with Ka-band multimedia system needs. The current design beam width is around 0.5° or larger, whilst the next generation of multiple beam antennas target beam width must be reduced down to 0.2° diameter, which requires a new feed design with reduced cross-section. This new highly compact RF chain also has to provide RF sensing capability in order to offer all the operational characteristics with respect to global multimedia mission requirements. The feed assembly could be placed anywhere in the focal plane, including in the middle of a feed cluster and thus has to have the same cross-section as a user feed chain without tracking system. This activity provided a trade-off between possible feed chain concepts and demonstrated the most promising through the manufacturing and test of an engineering model. The results achieved indicate the feasibility of a compact feed chain with tracking function fitting in a cylinder of 35 mm in diameter.

11:30 Coffee break

3 Miniaturized low-weight space antenna for AIS VHF applications (ARTES 5.1, 700 k€)

The ground based Automatic Identification System (AIS) is a coastal tracking and messaging system used by vessels for maritime traffic monitoring. The European SAT-AIS initiative aims at providing a space-based complementary system to extend the range of the existing AIS to high seas via VHF satellite constellation. The AIS Miniaturized Antenna (AISMAN) activity concentrates on the development of a VHF array antenna for mini-satellite platforms in Low Earth Orbit. Array element volume minimization and mass reduction are considered performance drivers due to the in-orbit array deployment and satellite mass requirements. Artificial Magnetic Materials (AMM) have been chosen as design concept of the baseline array element due to the significant size reduction they can offer. Further technical solutions, such as slotted ground plane, combined with AMM, have allowed for an outstanding profile reduction, while preserving high radiation efficiency and low back radiation. Innovative testing methodologies have been specifically developed to handle truncation errors and echo signals while performing radiation pattern measurement of the array on a full-scale mock-up platform in a hemispherical automotive NF range. This activity covered a trade-off on possible element designs, an array antenna trade-off and performance validation as well as a manufacturing and validation campaigns at single element and array level. A contract extension was awarded to investigate alternative manufacturing technologies and processes, leading to the manufacturing and testing of an additional engineering model based on a multi-layer stack assembly with metallic parts printed on a thin film material (Kapton substrate) and bonded to a core material made from RF transparent Kevlar Honeycomb.

12:45 Lunch Break

4 Ultra rapid deployable antenna (ARTES 5.1, 525 k€)

When disaster has struck, applying correct aid and relief work is critical, in particular within the first few hours and days after the event. In order to direct aid to where it is needed, there is a clear demand for communication infrastructure for emergency relief personnel (including disaster response agencies, non-governmental organizations, and private relief companies), security personnel and companies that require rapidly deployable, high-bandwidth satellite communications, including TV reporters. In disaster conditions, the availability of existing communication infrastructure cannot be guaranteed and there is a need for alternative ad-hoc links to exchange various vital data information from remote locations where other telecommunication infrastructure may be either inadequate or not available. This is true for first-response communications, as well as contingency communications and other short-to-medium term deployments. The Ku frequency band for satellite communication with its available bandwidth is well suited for all of the above scenarios. However, conventional Ku-band antennas tend to be large and difficult to transport or cumbersome to deploy, limiting their use in these situations. This activity has investigated a solution to this problem. A prototype antenna has been manufactured and field testing has been performed over satellite using a COTS modem to transmit and receive data. The initial requirements were: • performance equivalent to a metallic dish of at least 80cm diameter. • operation in Ku-band and be ETSI radiation compliant • to have set-up/take down time of less than 5 minutes (including pointing). • operational under heavy wind conditions. • when folded, the antenna shall have volume corresponding to about ½ a normal backpack.

5 Millimeter-wave VAlidation STandard (GSTP, 350 k€)

Inter-comparison and validation of antenna measurement ranges have been carried out for at least three decades. These activities allow finding and help correcting big and small problems in the facilities itself and the measurement procedures, thus leading to an improvement of the measurement accuracy and facilitating better understanding of the measurement techniques. The early experience gained demonstrated that dedicated VAST antennas are required for validation. These VAST antennas shall have the following characteristics: • Mechanical stability and stiffness over a given operational temperature. • Extremely stable electrical characteristics allowing frequent travel and handling of the VAST • A well-defined coordinate system, defined by dedicated alignment tools. The VAST-12 antenna, operating at Ku-band, has been used for many years but nowadays, many missions are using the Ka-band for user up/down links while the use of Q/V bands is contemplated for the feeder links in the coming years. To support this frequency band move, a VAST antennas at mm-Waves was required. The developed antenna uses the same mechanical concept as the VAST-12 but this time it is a multi-frequency reflector antenna: 20/30/38 and 48 GHz. There are adapters for Linear and Circular polarisation. The antenna has been designed, manufactured and tested by DTU electrical engineering department with assistance of TICRA and DTU Windenergy.

16:00 Closure