Sorry, but you got incomplete information. I checked your link and the
Raytheon radar is just a part of one of the systems produced by Sensis Corp.
(now Saab-Sensis).
The rotating antenna on top of the control tower is either an FAA ASDE-3
radar or an ASDE-X (Raytheon) radar. ASDE-X and ASDE-3X (using the FAA
radar) fuse data from radar and transponders, both airborne and on the
ground, into a position/altitude. The radar is an adjunct to TDOA and FDOA
(time and frequency difference of arrival of signals) geopositioning and
aids in position accuracy, but is not required to generate a position.
My statements come from prior work as Test Director during acceptance of the
ASDE-3X system at Louisville, KY (SDF). There are 30+ of these systems
worldwide at major and second tier airports.
The company that produced ASDE-X and -3X also setup systems in Colorado and
Alaska which allowed ATC to derive aircraft positions in remote areas which
have no radar coverage.
There were additions in the concept stage when I left the company that
included in-cockpit displays of traffic detected by the system but that was
over 5 years ago and I have no idea of whether they ever came to fruition.
But, like anything aviation related, it would probably cost both arms and
legs.
wrote in message
...
On Tuesday, December 10, 2013 10:19:07 AM UTC-8, Dan Marotta wrote:
Maybe someone should develop a device like the MRX PCAS which detects
transponders and includes azimuth in addition to range and elevation.
Most
of the algorithms have already been developed. There are well established
methods for very accurately locating a transponder. Look up ASDE-X, for
example (LAT/LON/ALT derived from transponder replies). Alas, I suspect
development cost would far outweigh expected return on investment.
I looked it up - ADSE-X is an active radar system that uses either a
rotating or phased array antenna (apparently normally mounted on top of the
control tower). It's not the sort of thing you'd find you could fit in a
glider - even if it were legal. Here's a long to a schematic of the
Raytheon version:
http://avstop.com/stories/asde.html
I am not aware of any system you could even adapt to put in a glider that
would allow you to get accurate azimuth information off of transponder
returns - even in theory.
9B