WI-FI SURVEYS

 When an IT manager, General Manager, CEO, or homeowner signs up for a wireless site survey, how is it beneficial to them? And what are the industry best practices in presenting the findings?

Most common best practices are to identify configurations that would negatively impact wireless network performance, and there are a number of findings that reveal problem areas 

such as:

• Identifying access points that are deployed for the wrong purpose -- An example would be using the incorrect models of AP's in many locations throughout a building. By having devices with omni-directional antenna's and installing the AP's at heights greater than 20FT would significantly reduce signal strength for devices connecting at floor level.
• Identifying RF cell overlap problems between access points -- Having omni-directional antennas on the AP's, there were too many RF cell overlaps between the AP's. As devices were connecting saw multiple AP's that were using the same channels, the wireless devices essentially had to wait in line to connect to that channel.
• Identifying a coverage void or null with outdoor AP's -- RF is a line-of-sight technology and having AP's mounted at various heights where the AP's were obstructed by walls, columns and or beams.
• AP power levels left at the default manufacturers configuration -- When all APs are broadcasting at the same power level, it can create interference with each other. This can lead to decreased performance and connectivity issues for users. By adjusting the power levels of each AP, you can help to reduce interference and improve performance.
• AP's installed/mounted at troublesome locations -- If an AP is installed in a location where there is a lot of interference from other wireless devices, such as microwaves or cordless phones, it can cause problems with the signal. This can lead to dropped connections, slow speeds, and other performance issues.

When one or more of these findings are implemented, Wi-Fi users generally see an immediate and dramatic network performance improvement in their wireless network.

From these findings, the wireless network design engineers will make recommendations that remedy as many of the problems as possible which includes:

• Deploy the correct access point models in the right locations. This means using omni-directional antennas in areas where there is a need for wide coverage, and directional antennas in areas where there is a need for focused coverage. It also means installing APs at heights that will provide adequate signal strength for the devices that need to connect to them.
• Reduce RF cell overlap. This can be done by adjusting the channel settings on the APs so that they are not using the same channels. It can also be done by adjusting the power levels of the APs so that they are not broadcasting too strongly.
• Fill in coverage voids. This can be done by adding additional APs or by adjusting the settings of the existing APs.
• Optimize AP power levels. As mentioned above, adjusting the power levels of the APs can help to reduce interference and improve performance.
• Install APs in less troublesome locations. If possible, avoid installing APs in locations where there is a lot of interference from other wireless devices.
• Use channel bonding. Channel bonding allows APs to use multiple channels simultaneously, which can improve performance in areas with high wireless traffic.
• Use a wireless controller. A wireless controller can help to manage and optimize the performance of multiple APs.
• Update firmware and drivers. AP firmware and drivers are regularly updated with bug fixes and performance improvements. It is important to keep them up to date to ensure optimal performance.

These are just a few of the recommendations that the wireless engineer can make to improve wireless network performance. The specific recommendations that are implemented will depend on the specific environment and the specific problems that are being experienced. 

1. An onsite visit with our expert wireless network engineer: (Don't overlook the importance of this, many companies are not capable of providing industry standard testing and expertise)

2. Manual inspection of wireless hardware: Leverage our specialists to solve complex technological problems in various environments, including where your devices are located and mounted.

3. Running wireless analysis software to capture data: From your existing Wi-Fi network, to make sure you have the best Wi-Fi service - both customer & corporate - with access to AirMagnet, kahau and other survey toolsets.

4. Assessment and analysis of data captured, and we will generate a full report document. 

• Purpose -- Why is the wireless survey being performed? What is the goal? (Often wireless surveys are conducted the determine if the RF coverage shown in a Predictive RF Design matches what's seen during the survey). (Other instances assessments review the current wireless network design and identify sources of ongoing performance problems).
• Scope -- What's included and what is not?
• Survey test infrastructure -- What hardware and software tools are being used to measure RF coverage? (For example, The Ekahau Site Survey Pro with the Ekahau NIC-300 USB Wireless adapters and an Aruba IAP-305 access point in survey mode).

5. The report outlines requirements as follows:

• SNR (Signal to noise ratio) minimum
• Signal strength minimum
• Data rate minimum
• Minimum number of access points

6. A floor plan listing routes -- for the site survey, and access point locations

7. Coverage and performance narrative: Survey Includes

• Data rate heatmap: for 2.4 GHz, 5 GHz and 6 GHz wireless frequencies (the highest speed a wireless device can transmit data)
• Maximum effective throughput heatmap: For 2.4 GHz, 5 GHz and 6 GHz wireless frequencies (Due to the current laws of physics RF works in half-duplex mode and true data throughput rate will be approximately half the data rate).
• RF signal strength/coverage heatmap: For 2.4 GHz, 5 GHz and 6 GHz wireless frequencies (the that can offer most basic measure of wireless networking health can often explain problems with unreliable connections and low data throughput.

8. Depending on the type of site survey, other metrics that may be included are:

• CCI (co-channel interference) analysis -- This identifies any crosstalk between two different transmitters on the same RF channel.
• ACI (adjacent channel interference) -- This identifies any extraneous power from a signal on an adjacent RF channel (In most wireless site surveys, a floor plan with access point locations, data rate heatmap, throughput heatmap, and signal strength heatmap is created for each floor in the building/dwelling)

TYPE OF SURVEY

• Predictive site survey - Before deployment - Coverage and performance 
•  Physical site survey - After deployment - Signal strength, interference 
•  Passive site survey - After deployment - Signal strength of all networks 
•  Post validation site survey - After changes - Performance of the network 

• Diagram/Floorplan with measurements of area to be surveyed (PDF file)
• Height of ceilings or roof
• Brand, make, model of Access points/Routers.
• Location of where the AP will be mounted ceiling/wall/floor.
• Type and thickness of building walls
• Wall closet to the switches/router etc, will be installed. Used for cable run estimates.
• Location of stairwells/elevators
• Will there be any exterior areas to be covered by Wi-Fi signals?
• Estimated number of devices that will connect to the Wo-Fi network