ISO/TS 21176:2020

Overview - ISO/TS 21176:2020 (PVT for C-ITS)

ISO/TS 21176:2020 defines a generic Position, Velocity and Time (PVT) service for Cooperative Intelligent Transport Systems (C-ITS). It specifies how PVT functionality is implemented in the ITS station (ITS‑S) facilities layer and how that PVT capability interfaces with other ITS‑S components (ITS‑S application processes and the facilities service handler). The Technical Specification standardizes PVT inputs, merged outputs, quality indicators and the service access point (SAP) primitives used by applications to obtain PVT data.

Key topics and technical requirements

• PVT service model: Generic reference model describing inputs, fusion/merging and PVT outputs with associated quality (e.g., accuracy).
• Positioning sources supported: GNSS (GALILEO, GLONASS, GPS), roadside infrastructure, cellular networks, kinematic sensors (IMU), vision/LiDAR sensors - implementations may use any combination.
• Facilities layer integration: How the PVT capability is integrated as an ITS‑S facility and its interface to other ITS‑S functions (per ISO 21217).
• Service Access Point (SAP) primitives: Function calls and responses (e.g., PVTinit, Get‑PVT, Subscribe‑PVT / Notify‑PVT / Cancel‑PVT) that ITS applications use to request or subscribe to PVT updates.
• Data types and encoding: ASN.1 module C‑itsPvt (Annex A) defines PVT-related types and value representations.
• Quality and conformance: PVT outputs carry quality indicators (accuracy, confidence). The document provides an implementation conformance statement proforma (Annex B). Note: formal conformance test procedures are out of scope.
• Optional capability mapping: Guidance for exposing PVT as an ITS‑S capability (see ISO 24102‑6).

Applications and who uses this standard

ISO/TS 21176 is intended for organizations involved in C‑ITS and vehicle/localization systems, including:

• Vehicle OEMs and Tier‑1 suppliers integrating positioning and ADAS/automated driving features
• ITS application developers (V2X services, fleet management, eCall)
• Map and location service providers, telematics and mobility platform vendors
• Roadside/infrastructure planners deploying C‑ITS infrastructure
• Test laboratories and integrators preparing PVT-enabled ITS stations and pre‑deployment pilots

Practical applications include geo‑stamping V2X messages, supporting lane‑level ADAS functions, merging multi‑sensor positioning for higher integrity, and exposing standardized PVT to diverse ITS applications.

Related standards

• ISO 21217 - ITS station architecture and facilities layer
• ISO/TS 17429 - Facilities Service Handler (FSH)
• ISO 24102‑6 - ITS‑S capability definitions
• EN 16803 series - GNSS performance/protection levels (assessment framework)
• CEN/TR 21186 - Guidelines for C‑ITS deployment

Keywords: ISO/TS 21176, PVT service, C‑ITS, ITS station, ITS‑S, GNSS, ASN.1 C‑itsPvt, service primitives, position velocity time, facilities layer.