08.15 D60038e0 Valid since standard implementation Rev. 01, subject to change

Data Sheet

P.1140 (Code 60038)

Speech communication requirements for emergency calls originating from vehicles

OVERVIEWEmergency call systems trigger an

automatic emergency call in case of an accident. For this purpose, technology based on hands-free functionality is used in the car. To ensure optimal communi-cation between the crashed car and the rescue service, appropriate measurement technology and test methods must be provided.

For this purpose, the ITU-T specification P.1140 has been developed. It provides test methods for verification of in-vehicle emergency call system conformity to specific requirements for loudspeaker communication in vehicle cabins.

With the measurement standard P.1140 for the communication analysis system ACQUA, HEAD acoustics has imple-mented tests for narrowband mea-surements as described in the ITU-T specification. It provides comprehensive tests for the analysis of

• Delay,• Double talk performance,• Echo,• Transmission behavior in

the presence of background noise (BGN).

P.1140 can be used by manufacturers and suppliers of the automotive industry to qualify and optimize emergency call systems.

DESCRIPTION The ITU-T specification P.1140 defines test methods regarding the speech intel-ligibility and communication efficiency of emergency call systems in vehicles. The requirements and measurements for the narrowband range described in this speci-fication have been implemented by HEAD acoustics for use with the communication analysis system ACQUA as measurement standard P.1140.

The P.1140 test suite thus allows the au-tomated analysis and experimental optimi-zation of in-vehicle emergency call systems (both built-in systems and after-market kits).

P.1140 comprises numerous standard values such as loudness rating, idle channel noise in sending and receiving direction, terminal coupling loss (TCLw) and echo attenuation. In addition, P.1140 takes into account several other important aspects:

• Tests under different conditions, e.g. vehicle environment (quiet street, heavy-traffic route), talker location (driver seat, seat next to driver or seat back from driver).

• Artificial head measurement system as “user” of the emergency call system.

• “Silent call”, where information is ob-tained from background noise picked up by the emergency call system.

• Variation of receiving loudness rating (RLR) in the presence of background noise (employing “Time-synchronous Noise Compensation” (TNC) technolo-gy).

• Primary focus on achieving a sufficient level of intelligibility and communica-tion efficiency.

APPLICATIONS• Automated analysis of in-vehicle

emergency call systems (built-in sys-tems and after-market kits)

• Experimental development and optimization of in-vehicle emergen-cy call systems

TEST SIGNALS• Real Speech• Composite Source Signals (CSS)• AM/FM modulated sine signals for

echo measurements

SYSTEM REQUIREMENTSP.1140 (Code 60038) requires the fol-lowing system components:• ACQUA (Code 6810 etc.), Ad-

vanced Communication Quality Analy-sis System, Version 3.3.200 or later

Note: existing customers need a valid software maintenance agreement (SMA)

• ACOPT 32 (Code 6859), Option Speech-based Double Talk

• MFE VI.1 (Code 6462), analog USB measurement front end with option MFE VI-BEQ (Code 6461)

• HMS II.3-33/34 (Code 1230.1/2), artificial HEAD Measurement System with pinna simulator type 3.3/3.4 and HIS-L (Code 1231), HEAD Imped-ance Simulator, Left.

Alternatively: HMS II.6 (Code 1389), with artifi-cial mouth and free-field microphones

• HAE-car (Code 6970), Background Noise Simulation, including required system components, e.g. labBGN (Code 6486), cf. corresponding data sheets

• PSB III (Code 6001), Pulse Splitter Box for synchronization of non-station-ary noise with ACQUA

• Radio Communication Tester, e.g. R&S CMU200 or R&S CMW500 (not delivered by HEAD acoustics)

Measurement tree and result diagram for P.1140 test suite in communication analysis system ACQUA

08.15 D60038e0 Valid since standard implementation Rev. 01, subject to change

represented by

MEASUREMENTS

The following list gives an overview of the measurements included in P.1140 test suite:

Measurement setup in car cabin

OPTIONS• CUU I (Code 6085), Adapter USB

<> USB for Remote Control HAE (Connection ACQUA PC <> HAE PC)

DELIVERY ITEMS• P.1140 (Code 60038), as ACQUA

database• V2C File (for ACQUA, Version

3.3.200 or later)• Documentation as PDF

*comprises several measurement variants, e.g. varying application forces