RTLS vs GPS: choosing the right location tech for indoor vs outdoor tracking

GPS is universal – until you enter a building.
RTLS is great inside – until the asset exits through the front gate. Making the wrong choice is expensive, but it also jeopardises the precision your entire tracking solution relies upon.

What they actually are
GPS

Global Positioning System

A satellite-based positioning technology in which a GPS module embedded within a tracker uses satellite signals to pinpoint location. Needs direct visibility of satellites – walls, ceilings, and other dense materials interfere greatly with the signal.

• Accuracy range of 3-5m outdoors
• Satellite-dependent
• RTLS

Real-Time Locating System

An indoor positioning infrastructure utilizing Bluetooth Low Energy (BLE), Ultra-Wideband (UWB), WiFi, or RFID anchors to locate assets through communication between tags and readers/anchors positioned throughout the building premises using RSSI, TDOA, and AoA algorithms.

• Accuracy range of 10cm to 3m indoors
• Infrastructure-dependent

Head-to-head comparison

Usage for each technology

RTLS - indoor application

• Hospitals
  Intravenous infusion devices, wheelchairs, emergency medical kits in various floors

• Warehouses
  Forklifts, pallets, bins within huge warehouses

• Manufacturing facilities
  Work-in-progress inventory tracking in different manufacturing process stages

GPS - outdoor application

• Fleet management
  Trucks, vans, delivery trucks traveling on roads

• Construction site
  Heavy machinery used at open construction sites

• Yard management
  Cargo containers and trailers in open yards

The hybrid solution

– what the majority of enterprise implementations utilize
Logistical and manufacturing operations do not operate within environments where assets remain exclusively indoors or outdoors. A pallet moves out of a warehouse, is put into a vehicle, travels to a distribution facility, and then heads back indoors. No single technology will account for the entire journey.

The solution: Utilize GPS for the outdoor/travel segments, while relying on BLE-based RTLS for the indoor segments, with the transfer occurring automatically when the asset crosses into a geofenced area. This transition doesn’t require any changes to the tag; today’s hybrid tags can accommodate both technologies and automatically switch between them based on signal strength.

Deployment advice: Always conduct a site survey before installing any anchor points in an RTLS deployment. The multipath effect caused by metal racks, machinery, and concrete floors can reduce precision by 40%–60% if anchors are placed without taking into account the RF environment.

Choosing an RTLS technology for indoors

RTLS isn’t created equally. If precision is your priority, then UWB is best, delivering up to 10-30 cm precision. However, it will cost you more upfront with higher costs per tag and infrastructure setup. BLE provides a good balance between performance and budgeting, offering a range of 1-3 meters, affordable tags, extended battery life, and versatile gateways which can serve as general IoT infrastructure. Wi-Fi RTLS utilizes pre-existing network components; however, the accuracy is lower (3-10 meters) and consumes network resources heavily.

Decision-making

Outdoor/mobile assets → GPS
Indoor assets → RTLS (BLE/UWB)
Indoor and outdoor/mobile assets → hybrid GPS/BLE tag
Indoor sub-30cm precision → UWB

Check out RTLS and GPS in practice. AssetTrackPro specializes in designing hybrid indoor and outdoor asset tracking solutions using BLE, UWB, and GPS technologies for logistics, manufacturing, and healthcare.

Learn more about AssetTrackPro ↗