Reconfigurable reflector for antennas and adaptive optics
An International organisation is offering a mechanically reconfigurable reflector for antennas, adaptive optics and laser communication applications. This technology consists of a reconfigurable reflector and has linear actuators having shafts protruding from the front surface operating on predetermined points of a reflective membrane and is fully based on standard technologies allowing significant reduction of costs and complexity.
An International organization is offering a technology based on a mechanically reconfigurable reflector adapted for reflecting radio frequency waves in a microwave antenna system. This technology was originally developed for space telecommunication systems but can be applied, with proper modifications, to any adaptive optics system which works by measuring the distortion in a wavefront and compensating for them with the use of a device that corrects those errors such as a deformable mirror. This kind of application can be found in optical microscopes and in high resolution retinal imaging but it also has large possibilities in laser communication systems, i.e. wireless connections through the atmosphere. The proposed technology consists in integrating, in a very compact and thermo-elastically stable way, a deformable reflective membrane and some linear actuators, together with the reflector supporting the structure itself.
Innovations & Advantages
The main innovations and advantages of the technology are summarized in the following:
• Use of only standard technologies which allows achieving high thermoelastic stability
• Minimization of the number of control points and actuators
• No impact in the overall volume and thickness since the actuators are embedded within the body of the reflector
• Minimum impact on the mechanical properties and stiffness of the reflector
• As the deformable membrane duplicates and overlaps the reflector front skin, remaining physically detached from it, it can be realized on the same mould used for the reflector shell curing process, thus facilitating the manufacturing process
• High cost saving for the overall system design and manufacturing
The proposed Reconfigurable reflector, as shown in the figure below, for radio-frequency waves can be adapted for reflecting radio-frequency waves. It includes:
• a rigid support element having a front surface;
• an elastically deformable reflective membrane lying over the front surface of the rigid support element;
• a plurality of linear actuators able to deform the reflective membrane by operating on predetermined points characterised by the fact that the linear actuators are embedded within the rigid support element and have shafts protruding by the front surface in order to operate on pre-determined points of the elastically deformable reflective membrane.
Current and Potential Domains of Application
This technology has been developed by ESA specifically for antenna systems used on-board of satellites. The potential domains of applications are various, the main applications concern:
• Adaptive Optics systems: it works by measuring the distortions in a wavefront and compensating for them with a device (for example a deformable mirror) that corrects the errors
• Laser communication systems: NASA is working on a similar concept concerning wireless connections through the atmosphere. They work similarly to fibre optic links, but the beam is transmitted through free space. A deformable membrane system could be used in laser communication systems in order to remove the effects of atmospheric distortion.