Testing of speech transmission quality and delay through the UE headset electrical interface is a common practice in the industry for troubleshooting and benchmarking of network and UE performance. The UE headset electrical interface provides a convenient access point for testing that removes acoustic interface related aspects from the measurement. Test equipment (TE) solutions designed to connect to the UE headset electrical interface are commercially available and target both "drive-test" as well as lab environment testing applications. However, the lack of a standardized test methodology causes difficulties in interpreting results between different TEs, leading to possibly misleading conclusions on both network and UE performance. The present document attempts to address this problem by providing a unified test procedure methodology.

The present document provides guidance on testing of speech quality and delay through a UE headset electrical interface, including both analog and digital headset interfaces. The present document includes test set-up configurations, measurement scenarios and an indication of a range of results that can be expected in measurements. It is envisioned that the present document will serve as a reference for UE vendors and Mobile Network Operators wishing to conduct such tests.