Study of eCALL

The DG eCall recommends that the following essential requirements for transmitting both voice and data through the mobile networks should be adopted:
1.Pan-European solution:
o Roaming capability
o Belonging to GSM Standards (ETSI, 3GPP) that must be available for long enough to support vehicle life cycle
o Commonly implemented by all European Telcos & within preferably all GSM modules
2.Real time transport mechanism
3.Quasi simultaneous voice call and data transfer
4.Secure transport and routing mechanism (E112)
5.Automatic Acknowledgement

The DG eCall recommends that the architecture for eCall, as illustrated in following figure, is adopted by all stakeholders when implementing eCall. The process is described below:
1) The eCall Generator initiate the eCall by sensors triggered and/or manually, send the in-vehicle
triggered eCall to a PSAP. The eCall consists of two elements: a pure voice (audio) telephone call
based on 112 and the minimum set of data (MSD)
2) The eCall (data + voice) carried through the mobile network, is recognized by the mobile network
operator (MNO) as a 112 emergency call, and is first handled by the MNO. Based on the 112
handling the MNO enrich the call with the CLI (caller line identification), and at the same time,
according to the USD and the E112 recommendation, add the best location available (based on the
best effort principle11). After the 112 handling, the telecom operator delivers the 112-voice together
with the CLI, mobile location and the eCall MSD to the appropriate PSAP.
3) The PSAP transmits an acknowledgement to the eCall Generator specifying that the MSD have been
properly received.