Prepare the Survey Around the Use Case
A site survey is the physical groundwork that sits between your deployment plan and any hardware purchase. Its purpose is straightforward: confirm what the actual environment looks like, measure how radio signals behave in that space, and produce a documented basis for placement, quantity and later calibration. Without it, you are procuring beacons against assumptions rather than conditions.
In practice, a site survey for a proximity or indoor navigation project has three distinct layers. The first is a structural assessment: ceiling types, wall materials, metal fixtures, glass partitions and anything that will attenuate or reflect Bluetooth signals. The second is an RF assessment: measuring the existing 2.4 GHz environment to identify interference from Wi-Fi access points, other BLE devices, microwave ovens or industrial equipment. The third is an operational assessment: footfall patterns, staff routes, temporary fixtures, power access for gateways or mesh nodes, and any physical constraints on where devices can realistically be mounted.
A desktop review of floor plans will not substitute for walking the space. Plans rarely show the metal ducting above a dropped ceiling, the promotional displays that appear each season, or the fire-rated bulkheads that prevent straightforward mounting. The survey is where those realities get recorded.
Who should take part depends on the organisation. At minimum, someone who understands the project objectives and someone who knows the building. In a museum, that might be the project lead and the facilities manager. In a retail environment, it could be the operations manager and a regional technician. If an integrator is involved, their surveyor should be on-site alongside your team, not visiting alone and reporting back later.
Measure Candidate Positions and Boundaries
Retail environments
Shop floors change frequently. Seasonal displays, promotional gondola ends and temporary stockroom reconfigurations all alter the radio environment. During the survey, note not just the current layout but the typical range of variation. Ask store managers what changes on a monthly or quarterly cycle. Mark fixed obstructions such as structural columns, chillers and lift shafts separately from movable ones. If the intention is to trigger notifications near specific product categories, measure signal behaviour at the exact fixture height and orientation you plan to use, not at an arbitrary point in the aisle.
Museums and galleries
Here the constraints are often conservation and aesthetics. Survey teams need to identify which surfaces can be drilled, which ceilings have accessible voids, and where cabling for any powered infrastructure can be routed without penetrating protected surfaces. Signal measurement should account for display cases, many of which contain metal framing or thick glass. Exhibits themselves may be moved or rotated, so document the current layout and the gallery's change schedule. If the project includes audio triggering, note ambient noise levels at each measurement point, as this affects content design rather than hardware but shapes where zones need to be drawn.
Event and temporary venues
Temporary spaces present a different challenge: the environment may not fully exist at survey time. In these cases, the survey focuses on the shell, the known infrastructure and the planned layout. Document power positions, rigging points, structural obstacles and the materials of temporary walls. Accept that final tuning will happen during build-up and build a calibration window into the project schedule. Measure the shell's RF baseline, then re-measure once staging, lighting rigs and AV equipment are in place, because those additions significantly change the interference picture.
What to measure and record
At each candidate beacon position, record the received signal strength indicator (RSSI) from a test beacon at your intended transmit power and advertising interval. Take measurements at multiple distances and heights, not just one spot. Note the device model and firmware version used for measurement, because different receivers behave differently. Photograph each location with enough context to find it again. Mark positions on a floor plan with a consistent numbering scheme that ties back to your notes.
For the RF environment, use a spectrum analyser or a BLE scanner capable of logging channel activity across the three advertising channels. Note any sustained high-activity periods, such as when a nearby Wi-Fi network is heavily loaded. If the venue has its own IT department, request a list of all 2.4 GHz access points, their channels and power settings.
Document Uncertainty and Next Tests
Surveying against a single moment in time
A survey conducted on a quiet Tuesday morning will not reflect conditions during a Saturday afternoon or a conference keynote. If the space has variable occupancy, revisit at least once during a representative busy period. People absorb and reflect Bluetooth signals, and a dense crowd can shift RSSI readings noticeably. This does not mean you need continuous measurement, but you should understand the range rather than treating one snapshot as definitive.
Confusing survey accuracy with deployment accuracy
The survey tells you how signals behave in the current environment with current obstructions. It does not guarantee that a production deployment will deliver a specific accuracy figure. Materials get moved, batteries age and firmware changes alter transmit characteristics. Treat the survey as a calibrated starting point, not a final specification. Any accuracy claim made to stakeholders should be framed as "measured during survey under these conditions" rather than a fixed operational guarantee.
Omitting the facilities team
Deploying beacons often requires access to ceiling voids, coordination with cleaning schedules and agreement on mounting methods. If facilities staff are not involved in the survey, you may discover during installation that your chosen positions conflict with fire suppression coverage, air handling maintenance access or electrical safety zones. A brief walk with the facilities manager early on prevents most of these conflicts.
Not documenting assumptions
Every survey involves assumptions: that a wall is solid brick rather than block, that a ceiling void is accessible, that a temporary structure will remain in place for six months. Write these down. When conditions change during deployment, the documented assumptions let you quickly identify which parts of the survey may no longer be valid and need re-measurement, rather than guessing.
Key checks before moving to procurement
- Every candidate beacon position has a recorded RSSI measurement at the intended transmit power and advertising interval.
- The RF environment has been scanned on all three BLE advertising channels and notable interference sources are logged.
- Fixed and variable obstructions are distinguished on the floor plan.
- Mounting constraints, including access, surface material and any conservation or safety restrictions, are noted per position.
- Facilities or building management have reviewed and signed off on proposed locations.
- Survey conditions, including date, time, occupancy level and measurement device, are recorded.
- Assumptions are explicitly listed alongside the findings.
When these elements are in place, the survey delivers what the next stage needs: a grounded, evidence-based specification that tells you not just how many beacons to order, but where each one should go, what transmit settings to use and which positions may need adjustment once live traffic is present. That specification then feeds directly into procurement and hardware selection, where the choices can be matched to the conditions you have actually measured rather than the conditions you imagined.
