[alma-config] Pseudo random arrays

[Al Wootten]

Reply-To: "David Woody" <dwoody at ovro.caltech.edu>
From: "David Woody" <dwoody at ovro.caltech.edu>
To: "Steven" <steven at heddle97.freeserve.co.uk>, <alma-config at zia.aoc.NRAO.EDU>
References: <001101c0dfb3$45d80960$06000007 at mojo> <3B054B11.F72DCCF1 at nrao.edu> <000701c0dfbb$767dacc0$06000007 at mojo>
Subject: Re: [alma-config] Pseudo random arrays
Date: Fri, 18 May 2001 14:03:18 -0700
Organization: Caltech
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The cos^2 pseudo-random antenna distribution in my memo is quite
different from what was analyzed by Steven in memo 353.  His cos^2
refers to the aperture pattern or autocorrelation of the aperture pattern,
I believe.  The cos^2 I was referring to is the large-scale distribution of
antennas and the analysis doesn't depend on the single aperture illumination
pattern.  Steven was trying to remove the sidelobes from close packed
antenna arrays while I am trying to understand the sidelobes from the
larger configurations.  Steven's memo clearly points out the very
detrimental
effect of having an underlying patterns in your antenna distribution or
UV coverage.  The pseudo-random arrays explicitly have no underlying
pattern just a large-scale probability distribution.
David
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