Site Survey

A site survey identifies the optimum locations for APs, given the access and bandwidth requirements outlined by the plan and design. It is important to note that a quality site survey is much more than a simple physical walkthrough of a school. An experienced network technician will use a combination of specialized electronic tools, practical experience and specific floor plans showing the locations of one-to-one learning environments. An effective site survey should indicate how many devices should be able to use the intended applications concurrently, and at what locations within a school building or buildings they can support. The original form of site survey was a combination of physical and trial and error. An AP can be placed in a possible location and tested for coverage, then added another and so on. Now automated, site survey tools exist to provide an initial plan for AP locations. These tools import floor plans from CAD files or jpeg files and allow users to overlay the APs in the software and generate a heat or coverage map to see if the coverage and capacity meets the system requirements. Most controller base wireless vendors have a system planning utility that can assist in this process.

When the site is surveyed, a report should be drawn up containing:

1 - The number of access points measured.

2 - Analysis of the physical structure, points where signal obstruction will occur.

3 - A report containing the best positioning of the access points.

4 - Determine how many simultaneous connections each access point will obtain for a specific SSID.

5 - Identify adjacent access points and channel planning (also known as channel reuse planning).

6 - Area coverage map indicating signal level, characteristics, coverage area throughput including, radio output power and signal to noise ratio (SNR).

This is an example of channel reuse planning.