Australia Telescope National Facility

This is a collection of the overheads presented at the above discussions on the possibility of a Luneburg lens as the SKA element antenna. The discussions included:

1. Luneburg lens overview (Graeme James)
2. Electromagnetic design options (Andrew Parfitt)
3. Trade-offs between materials, weight and size (John Kot)
4. A possible method of manufacturing the lens (Barry Parsons)
5. Observing the sky with the Luneburg lens – some issues for

It was shown in the overview that in many respects the Luneburg lens is an ideal solution for the SKA antenna problem. [Indeed, if the basic needs of the SKA can be satisfied (as was suggested by Ron Ekers) by a tracking multi-beam focal plane array together with a couple of independent pencil beams deployable relatively quickly anywhere on the sky, then the feed problem would not appear to be especially difficult.] The Luneburg lens is a structure that is readily analysed with several techniques possible (for more details see Andrew Parfitt’s talk). The main objections against the Luneburg lens were highlighted, such as materials, weight and manufacture, with solutions suggested. The major problem is one of manufacture and a possible to construct the lens was addressed by Barry Parsons. The sky coverage possible with the lens was discussed by John Bunton.

Arising from these talks and the subsequent discussions, it is clear that the immediate issues to address (and to be undertake in parallel) are:

1. the problem of manufacture, and;
2. a parametric electromagnetic study to establish an effective engineering solution.

Graeme James

21 September 1999