Survey
Multifloor survey

Special caution needs to be taken when surveying multifloor facilities. APs on different floors may be able to interfere with each other as easily as APs located on the same floor. It is possible to take advantage of this during a survey. By using larger antennas, it may be possible to penetrate floors and ceilings and provide coverage to floors above and below the floor where the AP is mounted.

In Figure , a four-story office complex needs to be covered. A single AP would not cover an entire floor. Mounting two APs on each floor would be expensive and might present a problem with APs on the same channel overlapping. Use patch antennas on the APs to solve the problem. Because the patch antenna is semidirectional, there is enough coverage from each AP to cover most of one floor and a portion of the floors above and below it. By mounting APs on alternating floors and at opposite ends of the building, the SE is able to achieve the desired coverage with only four APs.