Satellite Positioning for Fleets: Galileo Services and Signal Authentication

How Fleet Tracking Uses Satellite Positioning

A vehicle's position is one part of understanding its journey. Location, driver activity and the trustworthiness of navigation information answer different questions, so it helps to consider each separately. A position concerns where a vehicle is; an activity record concerns what the driver was doing. Authentication concerns the origin and integrity of the navigation message used for geolocation.

Galileo provides navigation, positioning and timing services, including an Open Service used in vehicle navigation systems. Its service descriptions also cover higher-accuracy positioning and navigation-message authentication. For fleet-related applications, these descriptions provide a useful framework for understanding the satellite contribution without attributing every tracking or record-keeping function to it. Smart tachographs offer a concrete example of satellite positioning appearing alongside a different kind of information: records of driving and other activity.

Galileo's Open Service and High Accuracy Service

The EU Agency for the Space Programme's Galileo service descriptions identify the Open Service as free navigation, positioning and timing for users worldwide. Smartphones and vehicle navigation systems are examples of its uses. Timing belongs alongside positioning in that description, although a fleet discussion may focus most visibly on the location of vehicles.

The High Accuracy Service, or HAS, is also free and globally available. EUSPA describes it as intended for applications needing higher positioning performance than the Open Service offers. The distinction is the positioning requirement of the application: a general navigation task and a task requiring higher accuracy pose different questions about the satellite service being used.

The descriptions establish the purpose and availability of these services. They do not, by themselves, specify the accuracy of a particular vehicle-tracking installation. An explanation of a service is therefore most useful when kept separate from a claim about an individual system's results.

Why Navigation-Message Authentication Matters

Galileo Open Service Navigation Message Authentication, abbreviated OSNMA, is a freely accessible data-authentication function for Open Service users worldwide. The European GNSS Service Centre's OSNMA explanation says it gives receivers assurance that a received Galileo navigation message comes from the system itself and has not been modified. This addresses the trustworthiness of navigation data, a different question from the higher positioning performance described for HAS.

OSNMA authenticates geolocation data carried in the I/NAV navigation message broadcast on the E1-B signal component. Authentication-specific data occupy fields that were previously reserved within the E1 I/NAV message. The Service Centre explains that using those fields introduces no system overhead and leaves Open Service navigation performance unchanged. Authentication therefore has a defined role within the navigation message rather than being described as an accuracy improvement.

The receiver is the point at which the assurance is provided. In practical terms, the question is whether the navigation message's origin and integrity have been authenticated. A record of driver activity asks something else. Keeping the two questions separate avoids treating authentication of satellite data as authentication of every item in a fleet record.

OSNMA Service Milestones

The OSNMA Public Observation Phase began on 15 November 2021 and continued until the Initial Service declaration. The Initial Service was declared operational on 24 July 2025. These milestones describe the service's progression; they do not establish the capabilities of any particular receiver or vehicle installation.

A useful receiver-focused explanation distinguishes the navigation message, the authentication data carried within it and the assurance supplied to the receiver. That keeps the discussion tied to the function described by the Service Centre. It also leaves positioning performance, message integrity and driver-activity recording as separate subjects rather than combining them into a single claim about reliability.

Satellite Positioning in EU Tachograph Rules

According to the European Commission's tachograph overview, tachographs record driving time, breaks, rest, other work and driver availability. Their purpose is to support checks on EU rules aimed at preventing driver fatigue and contributing to good working conditions, road safety and fair competition. This explains why a tachograph record includes more than vehicle location.

Installation is mandatory in new vehicles intended for goods transport with a mass above 3.5 tonnes, and in new passenger vehicles carrying more than nine people including the driver. From 1 July 2026, light commercial vehicles between 2.5 and 3.5 tonnes engaged in international transport for hire or reward must also have a tachograph installed. Both vehicle category and the stated transport activity matter to that description.

Regulation (EU) No 165/2014 sets the basic construction characteristics of tachographs and the main elements of the system that must be established and maintained across the EU. These requirements concern the recording equipment.

Smart tachographs securely record and store driver and co-driver activity using strong anti-tampering measures. They also record vehicle positions at certain moments using GNSS. The Commission describes position recording at particular moments, which should be understood separately from a continuous journey trace. The driver inserts a personal microchip card before driving; that card stores at least 56 days of driving activity and allows inspection authorities to retrieve the information.

The Commission also identifies a further development following Regulation (EU) 2024/1258 and forthcoming technical specifications: smart tachographs will be able to record and store data relating to occasional passenger transport. This is presented as a future improvement, so it should remain distinct from the existing functions described above.

Emergency Warnings as a Separate Satellite Function

EUSPA's service descriptions also cover the Galileo Emergency Warning Satellite Service, or EWSS. Its described function is to broadcast alerts globally, allowing national civil protection authorities to transmit directly to smartphones or other Galileo-enabled devices for emergency response and risk management.

That is an alerting function, distinct from positioning and navigation-message authentication. In a fleet context, the distinction helps organize the discussion: location services concern position, OSNMA concerns the navigation message's origin and integrity, and EWSS concerns warnings sent by civil protection authorities. The description of satellite warning delivery does not establish which warning functions are present in an individual vehicle system.