1. Reflector & Single Pixel Feed Panel Discussion
Offset Optics
SKA 2010, Manchester
Lynn Baker
23 March 2010
Lynn Baker SKA 2010

2. Advantages of shaped, offset optics
Clear optical path, low spillover, low edge illuminations.
High aperture efficiency and low noise temperature.
Low wide angle sidelobes
“Real estate” to mount feeds and receivers
Modest cost increase relative to symmetric paraboloid
23 March 2010
Lynn Baker SKA 2010

3. Example of 15 meter aperture design
23 March 2010
Lynn Baker SKA 2010

4. Design parameters
Clear optical path, low spillover, low edge illuminations.
High aperture efficiency and low noise temperature.
Low wide angle sidelobes
DVA-1.
23 March 2010
Lynn Baker SKA 2010

5. Physical Optics Analysis, Perfect Feed
23 March 2010
Lynn Baker SKA 2010

6. Comments & Caveats
Analysis is for a perfect feed and perfect reflectors
Corrugated horns can achieve close to this performance
Surface errors will increase sidelobes
Wide band feeds have reduced performance
See German Cortes talk on Wed. afternoon
23 March 2010
Lynn Baker SKA 2010

7. 12 Meter Conceptual Design, DVA-1
23 March 2010
Lynn Baker SKA 2010