How To Approach an APoS Survey

An APoS site survey is usually performed after a predictive model and is part of the design phase of a Wi-Fi project. It is used to study the propagation of a specific AP or antenna in order to adjust and refine the predictive model.

This type of survey requires time and a lot of equipment. It also requires some planning.

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What to do prior going onsite

Obviously, work on the predictive model (Design). From the design. Define which access point locations you would want or need to validate.

Document that information. In ekahau you could export an image outlying the AP to test by selecting the APs to test as “My APs”.

Create a brand new Ekahau project file dedicated to doing the APoS survey and upload it to the Connect account (if you have a Connect account)

Here is the information to gather before going onsite:

• Know the height of the ceilings. This will impact the equipment required to temporarily mount an AP
  • Cheaper tripods usually go up to 8-9ft (Example: https://amzn.to/2TTUzFW or https://amzn.to/38Sizxv)
  • Some tripods go up to 24ft (Example: https://amzn.to/2QjcELG)
    • Wheels
    • Add photos
  • If the ceiling is higher, you might need a skyjack. Do you rent one? Do you ask the customer for one? What about safety? Training or certification might be required.
• Safety & Security
  • Is a safety training required to be performing work within the facility?
  • Request access to the areas you need to study
  • See if access can be granted, if not, will they have an escort available for you?
• Scheduling
  • Does the customer have any scheduling restrictions? Perform the work off hours or when the facility is not in use.
  • How will this impact your work and how long it takes to make it work.

Prepare Your Equipment

The type of equipment used during an APoS should be identified prior to going on-site. Create a checklist for what you need to bring with you. Below are some of the items we have for APoS surveys.

• Access Points to be mounted temporarily
  • Use the exact same APs as the ones that will be deployed
  • You might need a model with internal antennas and a model that supports connecting external antennas
• Antennas that you want to try out
  • Don’t forget to bring a way to mount them temporarily. Bracket.
• Pole
  • Tripod
  • Painter pole
• A way to mount the AP onto the pole
  • Wi-Fi Stand: https://wifistand.com/ (Brackets: https://wifistand.com/collections/brackets)
  • Don’t forget about the external antennas
• A way to power the access point
  • Portable PoE+ battery (VenVolt or Accelerator)
  • Alternatives:
    • PoE injector powered by a portable battery (AC)
    • PoE injector with a long extension power cord
• Ethernet cables (plan for a long one if you need to mount the AP very high)
• Zip ties and Gaffle Tape (You never know) + a way to cut the zip tire
• A WLANPi (https://www.wlanpi.com/)
  • Typically if you need a DHCP server
  • Or if you want to do some sort of throughput tests

• Laptop
• Tablet with pencil (iPad if you use the Ekahau Connect iPad application)
• Sidekick & its charger
• External battery pack (the bigger the better). You can use it to charge your laptop (via USB-C) or ipad while you do your survey.
  • Big portable battery pack (USB-C 60W output): https://amzn.to/2J08UKF 
  • Smaller cheaper battery pack: https://amzn.to/3b6y722 
• Laser measurement device (60M: https://amzn.to/2QrB8Cu, 100M: https://amzn.to/2TXPEUz)
• Personal Protective Equipment (for some environments)
  • Steel Toe shoes or boots
  • Hard hat (https://amzn.to/39WTumA)
  • Yellow or Orange vest (https://amzn.to/3b5oHnO)
  • Hearing protection (https://amzn.to/3d9uaeU)
  • Safety glasses (https://amzn.to/2x87niY)
  • Harness (https://amzn.to/2Qo6gCB)
• Identification: the easiest is to use a name tag or a badge that you carry around your neck. You can re-use some of the ones you get at conferences (https://amzn.to/33pMUT)
• Chargers, adapters and cables (you can never have enough, bring backups)
  • USB to Lightning adapter if you need to connect the Sidekick to an older iPad. Try to use one that allows you to charge the iPad while having the Sidekick connected. Example: https://amzn.to/2WmxM7p
  • USB to USB-C adapter if you need to connect the Sidekick to a newer iPad Pro. Example: https://amzn.to/2QmVY5I
  • MicroUSB to USB-C cable if you want to connect the Sidekick directly to the iPad Pro. Example: https://amzn.to/2Uf6q0x
  • USB to USB-C if you want to connect your Sidekick to your Laptop (if you don’t have any USB ports). We like this 90 angle adapter: https://amzn.to/3b23gny
• Backups
  • Second Laptop
  • Second iPad (if you have more than one)
  • Second battery pack
• Water bottle

Once On Site

Depending on the environment, you’ll need to be aware of anything you’ll have to do before starting the APoS survey. Some environments want you to complete a safety training, for example, before stepping into something like a warehouse.

Safety tips:

• Make sure that you keep safely in mind as you bring your equipment within someone’s else work space
• When installing your AP on your tripod, make sure that everything is secured and is not going to fall and potentially injure someone.

Workflow:

• Try to define a game plan before starting your work
  • Based on the AP locations you need to test
  • Based on the AP model you need to test
    • Maybe start with the internal antenna location first
  • Based on the channels and Tx power level used
• Perform your measurements. Upload your data to Ekahau Connect
• Review the data in Ekahau Pro and adjust your predictive model
• Refine the next AP location to test
• Rinse and repeat

APoS Survey best practices:

• Configure one SSID per frequency band. This is not mandatory but allows you to easily visualize and compare RSSI coming from both frequency bands within Ekahau.
• Use the transmit power used in the design
• Walk far away from the AP so you can clearly define the coverage area
  • Be mindful of offsets
• If you use Ekahau, make sure you freeze your measurements before moving the AP
• To speed up the process, bring multiple APoS kits with you to perform parallel measurements

You need an easy and convenient way to adjust the configuration of the AP on the fly:

• Use an AirConsole left plugged into the AP
• Use a PoE battery with an Ethernet cable so you can easily configure the AP connecting your laptop
• Connect to the SSID configured on the AP and configure it via GUI