Do you remember that scene in the movie Forest Gump when “Bubba” goes on and on about the many different ways you can cook shrimp? Wireless Site Surveys are kind of like that.
No, there aren’t nearly as many as Bubba rattled off but there are quite a few and they all have their specific place in the wireless network design process.
Before we get into the various WiFi site survey types, it’s important to mention that site surveys are not the design process but merely a component in the process.
You can refer to our blog “Stop Calling a Site-Survey a Wireless Network Design” where we discussed in detail the real meaning of a site-survey and how to make sure you get the most out of your next design.
Here are the many faces of a site-survey; what they are for and when they should be used.
1 – Predictive Site Survey
Often misunderstood, this type of site survey offers cost and time effectiveness as well as being extremely accurate. Using both RF and specialized algorithms, a predictive site survey simulates RF in your specific environment.
From our experience this software has become very accurate and gives you an incredible view of their environment. When combined with an experienced wifi service provider, a successful design, even in high-density areas, can be achieved. The key to a good predictive survey is to have as much information as possible; we recommend using floor plans and building blue prints.
2 – Physical Site Survey
This type is highly recommended for more complex wireless objectives. This usually encompasses applications that roam from AP to AP and also tend to be latency sensitive. For example, RTLS in hospitals, wireless video surveillance and multi-media over wireless.
Typically with an on-site survey you use the predictive results to test them against the wireless design to prove that design in the real world, paying close attention to interference or noise. It’s important to simulate the applications that will be running on the network to make sure they work seamlessly.
3 – Passive
Used to collect RF data from all of the access points in a given area, these types of surveys are good for validating your design requirements. It allows you to plot WiFi heatmaps giving you a nice view of where your coverage spans and where there are holes at different levels.
Some of the main design elements a passive survey can help validate are primary and secondary RSSI, Interference (noise), SNR and co-channel interference.
4 – Post Validation
A wireless network design can be great on paper but real success is when it performs exactly as it should for what it was designed to support. A post validation site survey makes sure your new network is performing as it was designed to, using the requirements you established at the beginning of your design.
Testing and measuring every detail guarantees you can support your applications and processes successfully with your new network. Some areas to take a closer look at are: data rates, device to radio ratios, jitter, latency and QoS, high density areas and co-channel interference as well as other RF characteristics.
You can even use an application performance test to test your network from the application side of things for a unique view of your networks performance.
It’s important to understand the various types of site-surveys; to know when each is needed, and to make sure your next wireless network is successful. In doing so we're sure your stress levels will without a doubt go down.
With high quality analysis and detailed planning from using the right combinations of site surveys, you'll be confident knowing your wireless network will not meet your requirements but in most cases exceed them. Proper planning allows you to quickly adapt and address issues (should they arise) precisely and timely, meaning less stress on you!