Overview
Real-time location systems at industrial facility scale require different technology choices for different environments. This brief covers the multi-technology RTLS architecture for large facilities — the technology characteristics, deployment patterns, infrastructure design principles, and the ArgusIQ integration approach that unifies multiple location technologies into one operational view.
Technology Characteristics
BLE (Bluetooth Low Energy) — Indoor Zone Tracking
How it works: BLE readers (location anchors) are mounted throughout a facility. Tagged assets broadcast BLE signals at configured intervals; readers detect the signal and report signal strength (RSSI). The location engine determines which reader is receiving the strongest signal and assigns the tag to that reader’s zone. With higher reader density and AoA (Angle of Arrival) hardware, sub-meter accuracy is achievable.
Practical accuracy:
- Room-level (single reader per room): ±3–8 meters
- Zone-level (2–4 readers per large open area): ±2–5 meters
- Sub-meter (AoA readers, high density): ±0.3–1.5 meters
Reader spacing for zone-level accuracy in industrial environments:
- Open factory floor: one reader per 400–600 sq ft
- Enclosed rooms: one reader per room, plus readers at doorways
- Hallways and transitions: one reader per intersection
Tag specifications for industrial environments:
- IP67 minimum (withstands cleaning, moisture, pressure washing)
- Shock resistance for materials attached to assemblies or tooling
- 1–3 year battery life at 1-minute broadcast intervals
- Form factor appropriate for mounting method (weld stud mount, magnet mount, lanyard attachment)
- Signal penetration: BLE does not penetrate steel well; tag placement should provide line-of-sight to readers
Steel hull penetration challenge: In shipbuilding, BLE signals do not reliably penetrate multiple steel bulkheads. Each compartment effectively requires its own BLE reader. Interior spaces (engine rooms, void spaces, machinery spaces) need independent reader coverage rather than relying on readers outside the compartment.
Appropriate for: Indoor fabrication halls, outfitting areas, tool rooms, confined space entry points, healthcare (room-level equipment tracking), warehouse aisles.
LoRaWAN — Outdoor Long-Range Zone Tracking
How it works: LoRaWAN gateways are deployed on elevated structures (cranes, buildings, poles, towers). Tags communicate with gateways using sub-GHz radio (915 MHz in the US, 868 MHz in Europe). Location is determined by signal strength (RSSI-based zone assignment) or time difference of arrival (TDOA) with multiple gateways. LoRaWAN’s sub-GHz frequency provides far better range than 2.4 GHz BLE.
Practical accuracy:
- Single gateway (zone-level): the zone the tag is in, based on gateway assignment
- Multiple gateways (RSSI multilateration): ±50–200 meters
- TDOA with precision timestamp gateways: ±5–50 meters (requires specialized gateways)
Gateway range in industrial outdoor environments:
- Elevated mount (50+ feet): 500–1,500 meters line of sight
- Standard mount (20 feet, moderate obstructions): 200–600 meters
- Industrial laydown with cranes, equipment, and structures: 150–400 meters per gateway
Coverage design for large outdoor yards:
- Map the facility and identify elevated mounting structures
- Calculate coverage overlap needed for zone assignment confidence (minimum 2 gateways detecting each tag at each location)
- Typical shipyard laydown (1,000 acres): 8–15 gateways for zone-level coverage
- Gateway backhaul: Ethernet (preferred), cellular, or LoRaWAN backhaul (limited bandwidth)
Tag specifications for outdoor industrial:
- IP68 (fully waterproof; outdoor exposure)
- UV-resistant housing
- Operating temperature range for local climate
- 2–5 year battery life at 5–15 minute reporting intervals
- Tamper detection recommended for high-value assets
Penetration advantage: LoRaWAN’s sub-GHz frequency penetrates common building materials better than BLE. A LoRaWAN gateway outside a fabrication building may detect tags inside the building — though accuracy degrades with penetration through walls.
Appropriate for: Outdoor laydown areas, equipment yards, large facility grounds, covered outdoor areas, large indoor spaces with high ceilings.
UWB (Ultra-Wideband) — High-Precision Tracking
How it works: UWB readers use time-of-flight (ToF) measurement — the precise timing of RF pulse transmission and reception — to calculate distance between readers and tags. With 3+ readers in range of a tag, trilateration provides centimeter-level position accuracy.
Practical accuracy: ±10–30 cm typical; ±5 cm achievable with optimal reader placement and dense infrastructure.
Infrastructure density for production accuracy:
- One reader per 50–100 sq ft for ±15 cm accuracy
- Reader placement requires clear line-of-sight to tag; metal reflections degrade accuracy
- Ceiling-mount at 10–15 feet provides good coverage geometry
Tag cost and battery life:
- UWB tags are significantly more expensive than BLE tags ($50–$200 depending on features)
- Battery life shorter than BLE (0.5–2 years at active use)
Appropriate for: High-precision assembly workstations, tool tracking at precision assembly stations, confined assembly areas where exact position matters, calibration lab tool accountability.
Not appropriate for: Outdoor environments, large open areas (infrastructure cost prohibitive), confined spaces with significant RF reflections from steel.
GPS — Outdoor Mobile Assets
How it works: GPS receivers on assets calculate position from satellite signals. Standard GPS accuracy: ±2–5 meters with SBAS correction.
Coverage constraints: GPS requires clear sky view. Does not work reliably indoors, underground, or under metal structures. Shipyard cranes, covered storage areas, and building interiors are GPS-denied environments.
Battery and reporting considerations: GPS receivers draw significant power. Asset trackers combining GPS with cellular reporting have battery life measured in days to weeks (daily reporting) vs. years for LoRaWAN or BLE tags.
Appropriate for: Vehicles, mobile equipment (forklifts, cranes, mobile platforms), transportation between facilities, construction equipment in open field environments.
Not appropriate for: Indoor tracking, high-precision location, or static asset tracking where battery longevity is important.
Multi-Technology Architecture for Large Industrial Facilities
No single RTLS technology is appropriate for the full range of environments in a shipyard or large factory. The engineered approach uses the right technology for each zone:
Zone-Technology Mapping
Outdoor laydown areas, equipment storage: LoRaWAN (zone-level, 200–500m range per gateway, 3–5 year battery, IP68 tags)
Indoor fabrication halls (large open, high ceiling): LoRaWAN or BLE (LoRaWAN for large spaces > 50,000 sq ft; BLE for smaller enclosed areas)
Indoor outfitting areas and assembly (moderate size, lower ceiling): BLE (room/zone accuracy, adequate battery life, lower infrastructure cost than UWB)
Precision assembly workstations: UWB (for specific tool and component accountability at the station level)
Confined spaces (hull voids, tanks, utility spaces): BLE readers at entry points only (entry/exit detection rather than continuous interior tracking)
Mobile vehicles and transport equipment: GPS + cellular (live map view in Space Hub)
Integration in ArgusIQ Space Hub
ArgusIQ’s Space Hub serves as the unified location layer — each technology’s location data is ingested through IoT Hub (using the appropriate adapter for each RTLS vendor or protocol), normalized to the asset record in Asset Hub, and rendered on the Space Hub yard map.
The operations team sees one map. A structural module may be tracked by LoRaWAN when it’s in the outdoor laydown and by BLE when it’s moved into the outfitting hall. The zone assignment updates automatically as the module moves between coverage areas. The location history in Asset Hub records the zone transitions regardless of which technology detected them.
Infrastructure Design Principles
LoRaWAN Gateway Siting
Elevation: More is better. A gateway at 80 feet sees much farther than one at 20 feet. Existing shipyard cranes (100+ feet), building roofs, utility poles, and water towers are preferred mounting positions.
Spacing: Plan for 200–300 meter gateway spacing in dense laydown areas to ensure multiple gateways hear each tag (required for RSSI-based zone assignment with reasonable confidence).
Backhaul: Ethernet backhaul is preferred for reliability. Cellular LTE backhaul is acceptable at locations without Ethernet infrastructure.
Coverage verification: After installation, walk the coverage area with a test tag to verify that each location is heard by at least 2 gateways.
BLE Reader Siting
Zone boundaries: Place readers at zone boundaries (doorways, aisle intersections, zone transitions) to create clean zone assignment logic. A tag detected by a reader at a doorway is unambiguously in or approaching the zone on one side.
Height: Ceiling mount at 10–15 feet provides good coverage geometry in most industrial spaces. Avoid mounting directly on steel structures that may attenuate the signal.
Power: BLE readers require power. In facilities without ceiling electrical infrastructure, this is the primary installation cost driver. PoE (Power over Ethernet) readers where ethernet is available, or battery-powered readers with 3–5 year battery life for locations without power access.
Tag Selection and Management
Tag Registration Process
Every tag requires an entry in ArgusIQ’s Asset Hub before it’s deployed. The registration creates the device record (tag ID, tag type, battery specification, last-known calibration) and links it to the physical asset it will be attached to.
Automated registration workflows — scanning a QR code on the tag to create the device record and link it to a scanned asset QR code — minimize registration time in high-volume tagging scenarios.
Battery Monitoring
ArgusIQ Asset Hub tracks battery level for all managed tags (where the tag firmware reports battery level — most commercial tags do). When battery drops below the configured threshold (typically 20%), a PM work order is generated for battery replacement. For fixed-location readers, ArgusIQ monitors connectivity status — a reader that stops reporting is flagged for investigation.
Accuracy vs. Cost Trade-offs
The table below summarizes the practical design choices:
| Technology | Accuracy | Range | Tag Cost | Reader Cost | Battery Life | Best For |
|---|---|---|---|---|---|---|
| BLE RSSI | 3–8m | 20–50m | $5–$25 | $100–$400 | 1–3yr | Indoor zone |
| BLE AoA | 0.3–1.5m | 5–15m | $15–$60 | $200–$800 | 1–2yr | Indoor precision |
| LoRaWAN | 50–200m | 200–1,500m | $15–$50 | $300–$1,000 | 2–5yr | Outdoor zone |
| UWB | 0.1–0.3m | 20–50m | $50–$200 | $400–$2,000 | 0.5–2yr | High precision |
| GPS | 2–5m | Unlimited | $50–$300 | N/A (satellite) | 1wk–6mo | Outdoor mobile |
The right architecture uses the minimum technology cost to achieve the required accuracy for each use case — UWB where centimeter precision is required, LoRaWAN where outdoor zone-level accuracy is sufficient, BLE where indoor zone accuracy is adequate.
Talk to our team about RTLS design for your facility.