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I measured the antenna patterns from a Cisco AIR-AP1131AG-A-K9, by taking AirMagnet Survey Pro signal strength measurements in an open outdoor area. The AP was mounted vertically, like on a wall, or horizontally, as if clipped to a suspended ceiling grid, using both 802.11a and 802.11g.

The omnidirectional antenna pattern shown in Cisco Aironet Antennas and Accessories for the 1130AG internal antennas appears to be valid only if the AP is mounted in a horizontal position, and the plastic case top with Cisco emblem is toward the floor.

According to my measurements at approximately each 10 degrees around the access point, the azimuth pattern doesn't even approach being omnidirectional if the access point is mounted vertically, with the cables down (wall mount). The printed Cisco information is misleading, since it implies that the az/el patterns will be true regardless of the suggested vertical wall mounting or suggested horizontal ceiling mounting.

The antenna pattern files provided with LANPlanner were oriented correctly as originally supplied with LP 9.2.5.

Since I wasn't using an antenna range or anechoic chamber with calibrated equipment, you should confirm this information with your own tests before deploying these access points.

Charles Preston
Comsec Wireless
http://www.comsec-wireless.net