Which type of antennas are used in BTS in GSM?

Hi all,

I would like to know which type of antennas used in BTS in GSM system pls?

Someone has the refrence or document, pls upload it.

Nice day

Hi Leprof,

Attached please find some of andrew's.
http://www.repeater-builder.com/andr...guide-2008.pdf

Hadi