Table 1.
Comparison of indoor positioning technologies.
| Technology | Measurement Methods | Suitable Environment | Accuracy | Extra Device on User-side | Power Consumption | Cost | Advantages | Disadvantages | Examples |
|---|---|---|---|---|---|---|---|---|---|
| A-GPS 1 | TTFF 2 | Outdoor and Indoor | 5–10 m | No | High | Low | Reuse sensors embedded in smartphone or smartwatch; cover entire earth. | Low security; occupy channel resource. | Google Earth; Baidu Maps |
| GSM (cellular) | RSS 3 | Outdoor and indoor | 10–50 m | No | Low | Low | Free of same-frequency interference; reuse sensors embedded in smartphone or smartwatch [33]. | Low reliability [33]; privacy issues. | Google Maps |
| RFID | Proximity; RSS | Indoor | 1–3 m | Yes | Low | Moderate | Moderate cost; high accuracy. | Tags lack communications capabilities; positioning coverage is limitted; extral devices. | Cricket (MIT) [37] SpotON (UW) [38] RADAR(Microsoft) [39] |
| WiFi | RSS | Indoor | 1–5 m | No | High | Low | Reuse existing infrastructure; low infrastructure cost. | Fingerprinting systems recalculation [33]. | Nibble [40] Wayes [41] |
| UWB | ToA; TDOA | Indoor | 6–10 cm | Yes | Low | High | Excellent accuracy; effectively passing through obstacles. | High cost; short range; problem in non-Line of Sight. | Ubisense; Dart UWB(Zebra). |
| Dead Reckoning | Tracking | Indoor or Outdoor | 1–5 m | No | High | Low | No additional hardware such as beacons. | Low accuracy. | / |
| Infrared | Proximity; Differential Phase-shift; AoA 4. | Indoor | 1–2 m | Yes | Low | Moderate | Low power consumption. | Short rang; cost for extra hardware. | IR.Loc (Ambiplex) [42] |
| BLE Beacon | Proximity; RSS | Indoor and Semi-outdoor | 1–5 m | No | Low | Low | Low infrustructure cost; low power consumption. | Limitation in user mobility; low accuracy. | Shopstic (App). |
| Acoustic Signal | ToA; TDOA | Indoor | 0.03–0.8 m | No | Low | Moderate | No requirement for line of sight (LOS); does not interfere with electromagnetic waves [32]. | Cannot penetrate solid walls; loss of signal due to obstruction; false signals because of reflections [32]. | Active Bat; Sonitor IPS. |
| ZigBee | RSS | Indoor | 1–10 m | No | Low | Low | Low infrastructure cost; low power consumption; short time delay; high security. |
Short range | Best Beacon Match [43] |
| Visible Light | ToA; TdoA 5. | Indoor | 0.01–0.1 m | Yes | Low | High | Dual use of lighting infrastructure; compatible with RF sensitive areas. |
Needs to replace existing lights to LEDs 6 (dual use); High cost |
Bytelight; Ubeacon. |
| Image-Based IPS | Pattern recognition | Indoor | 0.01–1 m | No | High | Moderate | Relatively cheap compared with technologies such as UWB. | Requires LOS, coverage is limited | Sky-Trax; StarGazer. |
| Geomagnetism-based IPS | Maps matching | Indoor and Outdoor | 0.1–2 m | No | Low | Low | No requirement of the maintenance (reusing existing device); between sensor and source; the ability to penetrate walls. |
Interference by environment magnetic fields. | IndoorAtlas (University of Oulu) |