SBAS Ground Segment and Airborne Receiver Responsibilities
Purpose
This note separates responsibilities across the SBAS safety chain. It prevents ground-segment, service-provider, receiver, and operational-approval claims from being merged into one unsupported statement.
Responsibility split
| Layer | Typical responsibility | Evidence family |
|---|---|---|
| GNSS constellation | Base navigation signals | constellation/interface and ICAO/GNSS technical sources |
| SBAS ground segment | Monitoring, correction estimation, integrity-related processing, service monitoring | Annex 10 / Doc 9849 / service-provider documentation |
| SBAS broadcast path | Uplink and augmentation signal delivery | service-provider and standards evidence |
| Airborne receiver | Decode messages, apply supported corrections, compute/check usability, present modes/alerts according to approval basis | DO-229 and article-approval evidence such as ETSO |
| Procedure and operation | Decide whether a runway/procedure/aircraft/operator may use the capability | procedure-design, regulator, ANSP, AIP, aircraft, and operator evidence |
What the ground segment can prove
A service-provider or ground-segment source may support statements about system architecture, broadcast service, monitoring network, service definition, or performance reports within its scope.
It does not automatically prove:
- a particular receiver can use the service;
- a particular runway has an approved SBAS procedure;
- an aircraft installation is approved;
- an operator is authorized;
- a pilot may fly a specific operation.
What receiver standards can prove
Receiver standards and article-approval sources can support receiver capability and equipment-approval context within their scope.
They do not automatically prove:
- a regional service is available;
- a specific procedure is published;
- a state regulator has approved an operation;
- the service provider is meeting current performance commitments.
Why this matters
SBAS documentation often fails when it compresses the safety chain into one sentence such as “the system supports LPV.”
Institutional-grade documentation must ask: which layer supports what?
| Better question | Required answer |
|---|---|
| Is the technical service defined? | service-definition evidence |
| Is the receiver capability approved? | MOPS / ETSO / article evidence |
| Is a procedure published? | AIP/procedure evidence |
| Is aircraft/operator use authorized? | aircraft, avionics, operator, and regulator evidence |
| Is the service currently suitable? | performance/status and operational evidence |
Source anchors
- SBAS Core Claim Routing
- SBAS Standards Source Matrix
- Source - ICAO Annex 10 Volume I GNSS SBAS
- Source - ICAO Doc 9849
- Source - RTCA DO-229
- Source - EASA ETSO-C145e and ETSO-C146e
- Source - SBAS Service Providers
- SBAS Operational Validation Dashboard