en:c-its:messages:spatem
SPATEM (Signal Phase and Timing Extended Message)
SPATEMs transmit the current state of a traffic light (ETSI TS 103 301): which signal groups are red, amber, or green right now — and how the state is expected to change.
A SPATEM contains, among other things:
- the current phase per signal group (red / amber / green)
- predicted change times (e.g. “likely green in 12 s”)
- references to the intersection topology from MAPEM
SPATEMs are sent by C-ITS traffic lights (RSUs), typically several times per second. Together with MAPEM they enable time-to-green displays and speed advisories (GLOSA) — this is what some vehicles show as traffic light information.
en/c-its/messages/spatem.txt · Last modified: by fasteiner