ARTES-5.1 – ESA Telecom Technology Workplan ... - Emits - ESA

Annex 2Page 52Ref. Activity Title Procurement Policy Budget(KEUR)7-.017(09.153.21)Objective:Description:Planned TenderIssueAntenna radome for SATCOM user mobile terminals Open Competitive Tender Type: C1 400 3Q 2009 18Estimated Duration(months)To identify suitable radome materials for different mobile satellite ground user terminal antennas operating in Ku- or Ka-band. The activity includes the definition, build and testing of arepresentative radome prototype suitable for one type of ground terminal.Satellite communication antennas for ground applications require radomes to protect them from the outdoor environment. Ideally, these radomes are electrically RF transparent not to affectthe antenna radiating performance. In reality, the radomes do contribute to the antenna performance parameters, such as cross-polarisation, sidelobes, beamwidth and boresight pointing. Allthese performance parameters can vary significantly when the antenna beam is steered at low elevation. The challenge lies in limiting any performance degradation caused by the radome butstill fulfilling the other requirements imposed by the operational environment. The land mobile (automotive, train), maritime and aeronautical environment all present different requirements interms of possible shapes, structural strengths and allowable cost of the radome. The operational frequency and bandwidth also impose constraints on the material build-up. In Ku- and Kabandfor instance, water on the radome can significantly influence the RF performance and coatings to limit aggregation of water are of interest. Another issue that needs to be considered isheat dissipation through the radome. An antenna system typically contains a power amplifier that generates heat and which suffers from performance degradation if not allowed to dissipateheat adequately.Currently available radomes have shortcomimgs in one or more of the following aspects: ability to dissipate the heat generated by the transmitter inside the radome, ability to withstand theimpact of being hit by a bird when the vehicle moves at high speed such as a train at 300 km/hour, transparancy depends on the polarisation of the signal.The activity will investigate state-of-the-art materials, multilayer structures, metamaterials and RF techniques to minimize potential performance degradation while trying to reduce cost.Radome materials suitable for all types of user terminals, i.e. car, train, and airplane, will initially be considered through study and material sample realisation and measurement. A prototypemodel will be designed, manufactured and tested for one selected type of user terminal.In this activity, the contractor shall:- Expand and refine requirements for radomes.- Study and identify suitable material technology candidates for antenna radomes for Ku- and Ka-band and for the aeronautical, maritime and land mobile environment.- RF test these candidates at sample level.- Propose best candidates.- Design, manufacture and RF test a prototype radome for a selected environment (e.g. Ku-band maritime).