I would like some opinions on how to perform a site survey when surveying for both 2.4 and 5GHz.
Assume that the installation want good coverage on both 2.4 and 5GHz and that they use dual radio ap. Should I map one radio cell using 5GHz and then just assume that 2,4 will cover the same area and then some? Or should I do two walkabouts, one for each freq band and map them separately? I suppose the correct way would be to measure a cell twice, but time is money...
Does anyone have any experience on roaming between interfaces on the same AP? If I optimize both 2.4 and 5 coverage, then, in theory, the client could need to roam from 5GHz to 2.4 GHz.
Perhaps the best solution would be to identify power settings where signal strength on both 2.4 and 5GHz are equal.
A professional installer is needed for optimal results. These are the steps that are performed:
1. Obtain a facility diagram in order to identify the potential radio frequency (RF) obstacles.
2. Visually inspect the facility to look for potential barriers or the propagation of RF signals and identify metal racks.
3. Identify user areas that are highly used and the ones that are not used.
4. Determine preliminary access point (AP) locations. These locations include the power and wired network access, cell coverage and overlap, channel selection, and mounting locations and antenna.
5. Perform the actual surveying in order to verify the AP location. Make sure to use the same AP model for the survey that is used in production. While the survey is performed, relocate APs as needed and re-test.
6. Document the findings. Record the locations and log of signal readings as well as data rates at outer boundaries.
I agree that time is money, but saving on money during the pre-installation phase may cause you more money and more headaches than you bargained for down the road.
I have used to AirMagnet product, and their Surveyor is perfect for what you are doing, but it is pricy.
Regardless, I would do seperate surveys for 5 and 2.4. They are different in their distance and interference.
I had a few times that when I did a survey before we got the AirMagnet software, I just went around with a map and marked down my location and put the signal strength and quality in an excel spreadsheet, and put together a decent looking coverage map with Visio. You can do quite a bit without spending a lot of money, but it takes up a lot of time.
For customers that didn't want to spend the money up front, we just would over engineer the equipment and lower the power settings if needed. It seems easier to justify buying extra AccessPoints than spending money on a survey to the bosses. But I think that a good pre-install survey is absolutely necessary.
If you want to perform a site survey for both 2.4 and 5.0 Ghz at same time (as in, only walk the facility one time) you can also use Ekahau Site Survey software ( https://www.ekahau.com ) and use a dual mode card listed on their website. You can run the software on a laptop, but we use a Tablet PC and it works really well for that application.
The surveys should be done separately as the RF coverage is different for 2.4 and 5 Ghz. The 2 main differences are: 2.4 has only 3 channels that can be used without interference whereas 5 Ghz has many more and the cell size for 2.4 is larger than 5 Ghz.
This means the positioning of APs using 2.4 is more critical as you have to avoid same channel overlap but you may need more APs set to 5 Ghz to provide coverage across the whole site.