Wireless Site Survey Guidelines

this document aims to provide you with all the information required to perform a successful wireless site survey according to the nile guidelines let's break this down into 2 sections best practices to use during the site survey in terms of ap placements, use of radio power, height of the ap, capacity planning, secondary coverage, etc a checklist to follow before you upload the ekahau file to the site survey job, to make sure you haven't missed anything best practices nile slas are based on the network being redundant and resilient and to achieve this, one of the guiding principles that we use is to aim for a 67dbm secondary signal strength on the 5ghz spectrum design the wireless networks for the business use case find the least capable, most important ( lcmi ) in the customer's environment e g , barcode scanner at a warehouse, paging devices at a healthcare facility, laptops at a regular enterprise customer accommodate the applications that are using the networks as well e g , video/voip, cloud backups, dorm rooms with gaming consoles, etc, radio power configurations baseline tx power and eirp start with a 14 dbm eirp for 5 ghz and 8 dbm for 2 4 ghz in typical enterprise environments (height ≤ 12 feet) for high ceilings (above 12 feet), consider adjusting tx power (e g , 16–17 dbm for 5 ghz) to ensure adequate coverage but remain mindful of co channel interference eirp vs conducted power while we are at the topic of radio power, lets also understand the difference between eirp and conducted power effective isotropic radiated power (eirp) is the total amount of power that appears to be emitted by the antenna it takes into account the conducted power, and also the antenna gain eirp = conducted power + antenna gain conducted power on the other hand is the amount of power that is generated by a transmitter and fed into the antenna, in other way this is the power that we typically tend to configure on most of the survey tools ekahau in the tool, when we configure a radio tx power to be 9dbm, the tools automatically adds the antenna gain and there is a small text annotation that displays the eirp why 14dbm eirp? to answer this question, we need to understand the importance of tx power symmetry tx power symmetry between aps and devices is critical for optimal roaming and performance avoid excessively high tx power as it can lead to sticky clients (devices refusing to roam to a new ap when needed) stickiness can arise when aps are placed too high or the tx power is too strong, causing devices to stay connected to distant aps, resulting in slower speeds and poor roaming lot of the client devices radios are operating at a 12 14dbm power level, and hence if we operate close to those values, it can provide a better client experience while connected to our service also in some of the wireless zones, there is a cap on how much power the radios can emit, in those scenarios as well, if we start operating the radios at 14dbm, it gives our coverage hole algorithm some space to play around and increase the power levels to mitigate the coverage hole special considerations for deploying wifi6e (6ghz band) when deploying 6 ghz (wi fi 6e), opt for low power indoor (lpi) if operating in dense environments (e g , stadiums, conference halls) lpi mode allows the deployment of more aps but reduces power to avoid interference for standard power 6 ghz aps, be cautious as these require automated frequency coordination (afc) and higher eirp values plan accordingly based on afc availability for the best client experience on the 6ghz band, we need to ensure that the cell sizes for the 6ghz and the 5ghz bands are almost similar cell sizes typically get lower as we increase the frequency, so if all three radios on 2 4, 5 and 6ghz if they are operating at the same power level they will be in the following order 2 4 ghz >> 5ghz >> 6ghz so to ensure better client experience, we can start with the following eirp power levels in a typical high density enterprise office space 2 4ghz 5dbm 5 ghz 11dbm 6ghz 14dbm note these recommendations are for a high density carpeted office space, so please adjust the power levels according to the environment you are designing for by reducing the tx power, are we installing a lot more aps to a given coverage area? if we are looking at a typical enterprise office space, it is often the capacity that needs a closer look than the coverage any typical ap can easily cover up to 50ft of radius in an open space when deployed at 10 12ft high, but when we look at the latest enterprise carpeted office space designs, we see a lot of open desk designs, than the cubicles with each covering 50 100 sq ft and each desk has 2 devices at the least connecting to the network these will be categorized as high density wireless networks this sort of spaces often require close look at designing the network for their capacity needs than coverage so, even if we reduce the tx power, considering the capacity needs, we end up deploying enough ap's and not over compensating deploying the ap's in special environments for non standard spaces (e g warehouses, high ceiling areas, outdoor deployments) evaluate predictive surveys with increased tx power to compensate for the coverage loss outdoor ap's may require specific configurations based on mounting height (e g , 45 50 feet) ensure that they are placed in a manner that minimizes drop off at the edges of coverage secondary signal strength as you know nile has an incredible automation built into the channel planner, lets look at how this affects planning using the site survey tools when using ekahau/hamina, the secondary signal strength is purely the second highest rssi observed at any given x,y when all the ap's are operating at the same power level but with our channel planner, once the ap goes down, the bordering ap's to that region will be categorized as border ap's and will be increasing the tx power by 3dbm while, it is important to check the secondary signal strength, it is equally important to utilize the nile strength so that we can deploy less number of ap's suggested than what the tools suggest our recommendation would be to check for the secondary rssi after increasing the radio power of all the ap's by 3dbm and see if that provides the adequate coverage co channel interference and neighboring ap's if increasing the tx power, be sure to increase the distance between ap's to reduce interference for ap's placed at higher elevations (e g , above 28 feet), ensure they are spaced far enough apart (consider 25–50 feet depending on tx power) if you must exceed 14 dbm for tx power, ensure that ap's are sufficiently separated to avoid interference that degrades performance surveying multi storied buildings in addition to characterizing the walls on the floor, we also need to understand how the rf penetration is happening through the floor as well so, while performing the active ap on a stick survey, please navigate to the floor below and collect the data as well brownfield locations understand the current ap placement from the customer and generate a predictive survey to see if it matches nile standards if it doesn’t match the nile standards, then follow the steps outlined above to generate the ap locations sensor locations placement of nile physical sensors is a very important step that we need to identify during the wireless survey some general rule of thumb for the sensor placement should be around the perimeter of the building identify important areas in the floor like, executive rooms, big conference rooms, all hands meeting areas make sure there are working power outlets after a sensor location is determined checklist please make sure that the following items are present in the esx file and the report before closing the site survey job mobile app inputs set the scaling factor using a real time measurement and a large object at the site i e , length of a room, length of a hallway, etc as that will give us the accurate data draw the coverage area where wireless is needed and add any exclusion areas if applicable draw all the walls on the floor ap properties please make sure that all the simulated ap's in the ekahau file have the following properties mounting type wall mounting (vertical or horizontal mounting), ceiling mounting height access point height from the ground tags a template ekahau file will be provided in the appendix section of this document, which contains the tags that we need to use, more explanation on tags also will be in the appendix ceiling types these are nile specific and can be derived from the template esx file provided a note to be placed on the floor plan indicating “sensor location” generating report the final report must be generated after characterizing the signal attenuation from the different wall types that was found during the active survey in ekahau, navigate to reporting >> one click reporting bands 5 ghz floors select all the relevant floors paper a4 document format pdf sections coverage and performance signal strength secondary signal strength number of ap's requirements coverage and performance network issues requirements capacity capacity clients per ap access points my network access points notes map notes upload the esx file with the final location of the ap's with the above mentioned properties, tags, and notes to the site survey job