Questions about antenna array for WLAN applications

Urgent!
which kind of antenna is suit for constructing array in the wireless local area networks applications,especially meet broadband and compact needs?
All help would be welcomed,thanks!

More often circular or rectangular microstrip patch antennas will be used depending upon the type of polarisation required.
some of them used printed dipoles also...........

Thank you!
I want to let the antenna array operating 2.4GHz band with omnidirectional pattern and linear polarized ,so I suspect if the monopole antenna could be used to construct array.And I have read some papers about printed dipole-array antenna and collinear antenna to be used,I can't select that ,please give me some advices.