Summary

Recommendation ITU-T P.313 provides audio performance requirements for portable digital cordless and mobile handsets, headsets and speakerphone sets. The requirements apply to narrowband systems (3.1 kHz) regardless of the coding algorithm used in the terminal. Associated test methods are also given.

Requirements are specified for the major electro-acoustic performance parameters affecting audio quality, including sending and receiving levels, frequency responses, noise, sidetone, stability, echo path and delay. The requirements given in this Recommendation should ensure satisfactory service quality in a high percentage of installations under normal conditions.

Major changes over the previous version of this Recommendation (2007) are as follows:

•            Specifications for wideband handset, wideband headset and wideband hands-free terminals have been added;

•            The use of type 1 and type 3.2 artificial ears are removed from this Recommendation;

•            For handset terminals the test of speech quality in the presence of ambient noise has been added;

•            For most of the test point receive is now for the diffuse-field and no longer for ear reference point (ERP).

•            Requirements for some tests such as frequency response, distortion and linearity have been updated.