Mapping a Wi-Fi Network? 31
NivekEnterprises asks: "At my school where I am an Electrical Engineering major A Wi-Fi network has been set up, and is running in several buildings. Since the coverage extends outside several of my friends and I are trying to map the signal strength. Basically we are going to take a map of campus and walk around with a Wi-Fi enabled laptop, marking as best we can. Is there an easier way to do this? Has anyone else done something similar and is willing to share some their insights?"
Hmmm (Score:4, Insightful)
Wireless InSite (Score:5, Insightful)
There are several methods by which this could be accomplished.
The first is to create a link budget using the two-ray approximation [earthlink.net] (1/R^4 attenuation) and the estimated antenna patterns. This allows one to bound the maximum range as a function of antenna orientation and receiver sensitivity. Most likely this is the analysis that was done when installing the network.
A second and much more enjoyable way is to use a ray-trace simulation program such as Wireless InSite [remcominc.com] to model your campus. This model will pick up multipath effects and folliage losses.
The most time consuming but most accurate method is to walk around with an antenna, measuring the power as one goes. It should be noted that when one measures in a given location the power will change over time sometimes quickly. Known as Rayleigh fading, it is due to time-varying multipath from a dynamic environment.
I recommend tracking down a communications professor in EE and borowing their copy of Wireless InSite. If you pitch it right you could even get a credit of independent study from it.
Michael. [michael-forman.com]