Re: fwd: Re: Cylindrical arrays

On Thu, 2 May 1996, Christopher Smith wrote:

> ======== Original Message ========
>
> > From: CSMITH_at_MAXENG.delfin.com (Christopher Smith)
> > To: davem_at_ee.ubc.ca (dchatterjee)
> > Subject: Cylindrical arrays
> > Date: Fri, 26 Apr 96 09:54
> >
> > Amplitude taper in linear arrays to reduce sidelobes and beam width are
> > pretty well known. I suspect the phase taper corrects for the array
> > conforming to a cylinder.
> >
> > Chris Smith
> > Delfin Systems
> > csmith_at_delfin.com
> >
> > Chris,
> What I think you wanted to say is that
> amplitude taper reduces sidelobes and increases
> beamwidth. The phase taper does correct for a plane
> wave arriving at the circular array as is done for
> CDAAs.
>
> Bill Vail
> WAVE Associates, Inc.
> >
> >
> ======== Fwd by: Christopher S ========
> I guess I misstated it. You can apply a taper to a uniform linear array and
> reduce sidelobes at the expense of broadening the beamwidth, or you can
> reduce the beamwidth at the expense of increasing the sidelobes. And of
> course, the phase corrections for "bending" a linear array into a circular
> arc are a first order correction only.
> Chris
>

  I think that phase taper is simply correcting the phase of arrival at
  a distant point from the array (in transmission mode). The linear array
  concept was " bent " to determine the complex excitations because this
  was the best to come close to simulating the DBF technique. The
  simulation of the DBF technique is a main aspect of this work.

  Incidentally the results indicate that amplitude and phase taper together
  increase the " aperture length ". That is the far field observer sees a
  larger length than that which exists physically.

 =================================================================
  Deb Chatterjee

  Graduate Research Assistant
  Radar Systems and Remote Sensing Laboratory
  Department of Electrical Engineering and Computer Science
  Room 322, Nichols Hall
  2291 Irving Hill Road
  Lawrence, KS 66045-2969

  tel: (913)864-7742
  fax: (913)864-7789
  e-mail: dchatterjee_at_kuhub.cc.ukans.edu
Received on Fri May 03 1996 - 15:45:00 EDT