Acoustic Testing Advances for Next-Generation eCall Systems

In automotive safety applications such as emergency call (eCall) and next-generation eCall (NG eCall), the reliability of voice communication between the vehicle cabin and Public Safety Answering Points (PSAPs) is critical. As NG eCall over 4G (LTE) and 5G (NR) becomes mandatory in Europe from 1 January 2026, vehicle manufacturers and suppliers are intensifying their efforts to validate how well in-vehicle systems perform under noisy, hands-free conditions.

ANRITSU CORPORATION has introduced an acoustic evaluation solution designed for this requirement, developed in collaboration with HEAD acoustics. The system is intended for engineers responsible for testing emergency communication modules, audio subsystems, and telematics units, as well as those integrating NG eCall functionality into new vehicle platforms. The solution is compliant with ITU-T Recommendation P.1140, which specifies methods for assessing hands-free communication equipment in vehicles.

Acoustic Challenges in Emergency Situations
During a collision or other emergency, the voice link between occupants and PSAP operators must remain intelligible despite the challenging acoustic environment inside the vehicle cabin. Road noise, wind, engine vibration, and echoes can interfere with conversation, while hands-free operation can introduce additional variability. These factors complicate the transmission and reception paths and can reduce the clarity of information shared during the critical first minutes after an incident.

By enabling controlled and repeatable testing, the new acoustic evaluation setup allows technical teams to examine how these conditions affect both the microphone (uplink) and speaker (downlink) audio performance.

Integrated Cellular and Acoustic Testing Architecture
The solution combines Anritsu’s cellular network simulators—MD8475B for LTE base-station simulation and MT8000A for both LTE and 5G NR simulation—with HEAD acoustics’ ACQUA analysis platform. This setup allows laboratory testing of NG eCall communication quality without relying on live networks, ensuring that latency, radio conditions, and codec behavior can be studied systematically.

ACQUA provides detailed measurements of voice quality parameters, while the network simulators reproduce the communication path conditions found in operational LTE and 5G networks. Engineers can conduct standardized tests aligned with P.1140, enabling objective comparison across vehicle models or hardware versions.

Testing Under Realistic Cabin Conditions
A key requirement for NG eCall validation is the ability to analyze audio performance under noise and echo conditions representative of actual driving. The solution supports scenarios such as echo or double-talk, where the signal from the speaker may re-enter the microphone or where two talkers speak simultaneously. It also allows the emulation of cabin noise, including road, wind, and powertrain sources, helping assess how much environmental noise influences speech intelligibility.

Because these scenarios can be recreated consistently, manufacturers obtain repeatable data to guide hardware adjustments, microphone placement, speaker tuning, and software-based echo-cancellation strategies.

Supporting Development of Safer Vehicle Communication Systems
By integrating acoustic analysis with cellular network simulation, the solution provides a structured and measurable approach to validating NG eCall voice communication. This helps engineers verify whether communication modules perform reliably when the vehicle is operating under acoustic stress, thereby supporting compliance with the upcoming 2026 regulatory requirements.

Through this collaboration, Anritsu contributes to the development and refinement of in-vehicle emergency communication systems, which remain a key element in improving response times and enhancing overall mobility safety.

www.anritsu.com