Introduction

This workshop and preparation for this talk have presented a nice opportunity to take a long range look at the problems of interference, spectral baseline distortions, and antenna efficiency, particularly in connection with large sky surveys. My comments may be a bit too long range to be of very much immediate benefit to the Parkes multibeam surveys.

Improvements in interference immunity and spectral baselines cannot rely heavily on post-observation data analysis. We need a much better understanding of antenna far-sidelobe structure and of the temporal and spatial properties of interference. The next big step in multibeam array efficiency requires a jump from our present one-feed-one-beam arrays to closely spaced arrays of small elements whose signals are combined to form more efficient, overlapping beams on the sky.

© Copyright Astronomical Society of Australia 1997