Complete text of FCC rules about certified antennas and equipment:
http://gullfoss2.fcc.gov/prod/ecfs/retrieve.cgi?native_or_pdf=pdf&id_document=6516285598
Radiolabs.com article on antennas and different types:
http://www.radiolabs.com/Articles/wifi-antenna.html
The Cisco website contains detailed information about its complete line of antennas:
- 2.4-GHz antennas:
http://www.cisco.com/en/US/products/hw/wireless/ps469/products_data_sheet09186a008022b11b.html
- 5-GHz antennas:
http://www.cisco.com/en/US/products/hw/wireless/ps469/products_data_sheet09186a008022fb7f.html
