WiFi Survey Methodology

Some vendors conduct a “professional” WiFi survey by walking around your office with an Android phone or tablet using an application like WiFi Explorer to see what the signal strength is in various areas of your facility. While this is a suitable method for tuning and quick troubleshooting, it is not a good tool for doing an in-depth survey for design or troubleshooting.

What we outline below is considered to be the best possible survey. Some parts can be modified or eliminated but the end result could change some. It is the client’s decision as to level of accuracy of the survey desired. We will make sure you are aware of the differences so you can make an informed decision.

We conduct our surveys using industry standard methods and enterprise grade tools. We start our survey with a clean copy of your floor plans. Hopefully accurate, but if not, we can make minor adjustments as we go along. We load them into our survey software (Ekahau Enterprise Site Survey). If you have an existing WiFi network or have neighbors surrounding your facility with WiFi, we conduct a walk through gathering data on the existing environments.

Ideally we can get access to every corner of your facility. Our test laptop reads and records all WiFi networks broadcasting on 2.4GHz and 5.0GHz. It records the signal strength and noise, can calculate the ping time and test bandwidth, and much more. We also conduct a dual-band spectrum scan looking for interference that might cause challenges with your deployment. We run our test laptop with 3 testing NIC cards (reduces capture time to 1/3rd normal thus allowing us to move a little faster). We also use 2 WiSpy spectrum analyzer antennas to allow dual-band scanning and recording.

For more intense environments we have a highly sensitive RF Explorer to scan the spectrum from 50Mhz up to 6GHz.

After we finish the walk-through scan, we select a few locations to test for specific WiFi coverage and signal loss. We use these tests to validate our readings and to help us set up the predictive design properly. To test the loss rate of various obstructions, we place an access point on a portable mount on one side of the obstruction. We take multiple test readings on both sides of the obstruction at the same distance from the access point. We calculate the difference between the readings so we know what affect the obstacle has on signals. When we draw in the walls on your floor plan, we use those settings to make it more accurate.

After we have gathered our measurements, we build out your floor plan. Ekahau allows us to trace your walls and set the loss rate for each one. Next we use Ekahau to place access points in the best locations to provide the level of coverage you need. We place the same access points you plan on using. Ekahau has a library of over 5000 different access points and antenna combinations. We can move them around as needed to find the best layout.

Once we have a solid design plan, we come back through and conduct some AP on a Stick tests to make sure the plan matches reality. We place our test AP at some of the mounting locations. Our normal rig can be extended to most normal ceiling heights and it can also be used to mimic wall mounts. After placing the AP, we use our test laptop to walk the area we predict will be covered, and slightly beyond. We compare the results against the original predictive design. If they are a match, we stop there. If not, we make adjustments as needed.

After the survey work has been completed, we document our results in a comprehensive report. This includes our test readings, recommendations, and potentially power setting and channel recommendations, depending on your needs. Our report might also include a network assessment and recommendations for materials if requested.

We strongly recommend conducting a post install survey as well to make sure your final install is correct. These post install surveys can also be used to make channel and power setting changes.