Triton_Mgn says,,,   Good afternoon, give the antenna a good antenna for the 1800 MHz mimo 
Found 2 antennas on the forum:

1 - http://www.lan23.ru/forum/showthread.php?t=12671
But, unfortunately, not its size at the desired frequency, tell me who knows.

2 - http://www.lan23.ru/forum/showthread.php?t=10879
Could you tell me the thickness of the disc, can I use galvanized?
In the drawing, the antenna of this size for the lower frequency 1747,5 pink color,
and upper 1842,5 green. Why, then, in the drawing there are dimensions in blue?     My answer is,, it can build a patches antenna instead of a disks, a horizontal patch antenna group (at one end of the frequency band) and the other group with vertical polarization (at the other end of the frequency band)