[RockyTx]

what does ‘secondary’ radar mean?
(or primary)
..............
with transponder turned off.
how does radar determine height?

[Jack Hydrazine]

http://en.wikipedia.org/wiki/Secondary_surveillance_radar

[Jack Hydrazine]

Whats the difference between primary and secondary radar systems?
http://answers.yahoo.com/question/index?qid=20130617055124AABiqhS

Radartutorial.eu
http://www.radartutorial.eu/02.basics/rp05.en.html

Radartutorial
Book 2 „Radar Sets“
http://www.radartutorial.eu/druck/Book2.pdf

Difference between primary and secondary radar
http://www.youtube.com/watch?v=7Tp-vdz2x2A

[eyedigress]

3D RADAR goes back to the 60’s. Where a pulse is transmitted from a multi-feedhorn is only received from a barker-encoded signal to that feedhorn in an integrator type of receiver.

That information can be further analyzed due to signal strength as to what angle had the greatest return.

This gives you altitude. Azimuth is a given.