[Antennas] Passive reflectors

[Richard Barth]

Back-to-back dishes is another type of passive reflector and is
preferable in some cases,
typically where the end points of the link and the repeater site are
more or less in a
straight line.  If the repeater site can be chosen so that the included
angle from there
to the two end points is fairly acute, a billboard is probably a better
choice because
you don't have waveguide losses and the antenna (reflector) area can be
made larger.  
In a straight-line situation, you also have the choice of using two
billboards, each one
serving to bounce the signal from an end point to the other reflector. 
As in many cases,
that's what you pay the designer for: to worry about things like that.

Dick

antennas-request@mailman.qth.net wrote:
 
> Message: 2
> Date: Sun, 03 Aug 2003 18:49:36 -0700
> From: Harvey&Bessie <w4tg@bellsouth.net>
> To: Richard Barth <Richard.Barth@noaa.gov>
> Cc: antennas@mailman.qth.net
> Subject: Re: [Antennas] Passive reflectors
> 
>         When I was engineering a project in Puerto Rico we needed a microwave link between Fort
> Allen (Losey Field) and Salinas that was masked by a hill. I proposed a "billboard" type
> reflector on the hill to get the link down into the site. We let the contractor do the
> design work and he came up with a tower and two dishes connected by waveguide that worked
> very nicely. That was many years ago (late 50's) so I no longer have any of the details.
> 
> Harvey/W4TG