Glossary · Location
Wi-Fi positioning
Wi-Fi positioning estimates where a device is from the Wi-Fi networks it can detect nearby, using the identifiers and signal strengths of those networks. The device does not connect to them. It works indoors, where satellite signals are weak, but it only says roughly where, not exactly.
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How does Wi-Fi positioning work?
Wi-Fi positioning works by matching a scan to a map of known networks. The device listens for nearby access points and notes each one's hardware address and how strong the signal is. It never joins the network and never needs a password.
- 1
Scan
The device lists the access points it hears, with a signal strength for each.
- 2
Match
The list is compared to a database that records where those access points were seen before.
- 3
Estimate
The match gives a position and a margin of error. More networks, and stronger ones, narrow the margin.
The database can be a public service or one the system builds itself by remembering what a site looks like on earlier visits. The second is often called Wi-Fi fingerprinting.
When does Wi-Fi positioning work well, and when does it not?
| Setting | Result |
|---|---|
| Inside a building near other buildings | Usually good: many networks to hear |
| A new building with no Wi-Fi yet | Weak or none: nothing to match |
| A moving vehicle | Unreliable: scans are short and sparse |
| A remote site far from any network | None |
What does Wi-Fi positioning do on a jobsite?
On a jobsite it fills the gap where satellite positioning struggles: inside a half-built structure, a parking garage or a trailer. A badge that scans for Wi-Fi inside a building and reports the result can still place a worker at the right jobsite when GPS cannot.
ZeroBadge uses GPS outdoors and Wi-Fi positioning indoors, and learns each site's Wi-Fi over the first visits. It answers which jobsite, not which room. See GNSS for the outdoor side.
