Overview
ISO/IEC 24730-2:2012 specifies the Direct Sequence Spread Spectrum (DSSS) 2.4 GHz air interface protocol for real time locating systems (RTLS). Part of the ISO/IEC 24730 series, this standard defines the radio beaconing, message formats and basic behaviours for networked RTLS transmitters (tags), readers and reference tags that provide X–Y coordinates and telemetry. It targets RTLS deployments operating in the internationally available 2.400–2.4835 GHz band and is intended for frequent updates and approximate location (typical accuracy ≤ 3 m).
Key topics and technical requirements
- Air interface: Defines a DSSS-based 2.4 GHz beaconing protocol for RTLS transmitters and reference tags.
- Beaconing / tag blink: Transmitters autonomously generate spread‑spectrum beacons (blinks and sub‑blinks).
- Frequency & power: Operates in 2.4 GHz ISM band; Class 1 transmissions are low power and co‑exist with IEEE 802.11 WLAN and ISO/IEC 18000‑4 devices. Class 1 EIRP shall not exceed 10 dBm where applicable; Class II limited by local regulations.
- Range & performance: Transmission power and parameters enable at least 300 m line‑of‑sight (LOS) reception under specified conditions. Each receiver must be able to process a minimum of 120 beacon transmissions per second.
- Location accuracy: Nominal RTLS location data shall be within a 3 m or less radius of the actual transmitter location.
- Device roles: Defines RTLS transmitter (battery tag), RTLS reader, RTLS reference tag (always‑on for synchronization), RTLS server and RTLS infrastructure.
- Location methods: Supports algorithms based on ToA, TDoA, RSS (triangulation/multilateration), and AoA - reader synchronization for timing methods is specified in related parts.
- Manufacturer ID: Manufacturer tag identification is a 16‑bit field allocated per ISO/IEC 15963.
- Modes: Supports field‑programmable transmitters and an optional exciter mode that can modify update rate or location behaviour (mode defined but not the control mechanism).
Applications
- Asset tracking and inventory management in warehouses, hospitals, airports, campuses and industrial sites.
- Use cases requiring frequent location updates (several times per minute) and sub‑3 m accuracy for mobile assets or personnel.
- Integration with asset management systems and telemetry feeds for operational analytics, safety and workflow optimization.
Who should use this standard
- RTLS hardware manufacturers (tags, readers, reference devices)
- System integrators and solution vendors deploying DSSS 2.4 GHz RTLS
- Enterprise IT, facilities and asset management teams specifying interoperable RTLS solutions
- Test labs and certification bodies validating conformance and RF coexistence
Related standards