PAGE CONTENTS
Objectives
With the rapid increase in demand for high data rate communications among mobile users, there is a considerable and increasing demand for systems operating at higher frequencies where bandwidth is more readily available to deliver the data rates needed. Antenna design is particularly challenging in Ka-band due to tolerance issues and increased losses and as a result there are very few competitors offering systems based on flat panel array technologies.
The objective of this programme is to demonstrate the application of novel antenna technology to enable the aperture size, in particular its height, to be reduced as far as possible whilst maintaining the required performance. The project has produced a demonstrator antenna to an advanced prototype standard which is sufficiently representative of production units to allow preliminary qualification of the design.
Challenges
The ohmic losses in the antenna must be minimised in order to maintain gain and G/T whilst reducing the aperture height considerably compared with conventional reflector technology. In addition, the sidelobe templates are stringent in order to minimise interference to other satellites. The relatively high frequency means tight tolerances must be maintained in order to avoid degrading the performance of the antenna. The aperture should be common to receive (20 GHz) and transmit (30 GHz) bands to use all the limited space available for maximum performance, requiring a broadband antenna design.
Also key is the mechanical robustness and thermal stability of the antenna. The antenna includes relatively large, unsupported areas, which must not distort during the manufacturing process or during operational service under harsh shock and vibration conditions and wide temperature extremes.
Plan
WP1000: Business Development
Detailed requirements definition and specification fine-tuning.
WP2000: Outline Antenna Design
Top-level antenna architecture design including performance predictions and mechanical layout.
WP3000: Assessment of Manufacturing Options
Evaluate options based on cost, tolerances, performance, environmental stability etc.
WP4000: Feed Chain and Azimuth Beamformer Design
Detailed design phase.
WP5000: Elevation BFN and Radiating Structure Design
Detailed design including elevation amplitude taper, power splitters, radiating aperture.
WP6000: Polariser Design
Detailed design phase.
WP7000: Mechanical Breadboard Design, Manufacture and Test
Preliminary mechanical stress and thermal analysis/test.
WP8000: Design, Manufacture and RF Test of Complete Ka-Band Antenna
Prototype antenna manufacture/test.
WP9000: Project Management
Current Status
The project is complete: the antenna has been designed, constructed and successfully tested.
Companies
