ITU-T P.1140 PDF

This Recommendation1 defines use cases, requirements and associated test methods for the speech communication for emergency call communications originating from vehicles using a dedicated emergency call system. This covers:

- built-in emergency call systems (manufacturer installed)

- after-market emergency call kits.

For test purposes, the test set-up and the recommended environmental conditions are described.

This Recommendation addresses the test of complete systems and covers the following use cases:

- The call is originated either automatically (or possibly manually) in the accident, in hands-free mode.

- The call is between the vehicle from where the emergency call is originated and the nearest PSAP.

- The requirements take into account talking and listening from all locations in the vehicle cabin.

- The requirements take into account "silent calls", where information is obtained from background noise picked up by the emergency call system.

- The requirements focus primarily on achieving a sufficient level of intelligibility and communication efficiency.

The methods, the analysis and the performance parameters described in this Recommendation are based, where applicable on test signals and test procedures as defined in [ITU-T P.501], [ITU-T P.502], [ITU-T P.340] and [ITU-T P.1100].

This Recommendation in principle covers speech communication requirements and tests for emergency call systems in narrowband and wideband mode. However, this version of the Recommendation covers narrowband only, wideband is for further study.

This Recommendation addresses the crash situation by simulating a post-crash situation as realistically as possible with respect to the impact of a post-crash situation on the acoustical environment. It is assumed that the performance of an in-vehicle system (IVS) after a crash is adequately covered by simulating a post-crash situation in an un-crashed car, provided that the system is still functional and the acoustical elements remain at their original locations. Specific tests after a car crash are not within the scope of this Recommendation.