Technical Committee (TC) Speech and Multimedia Transmission Quality (STQ) Activity Report 2021

Chair: Scott Isabelle, Amazon

Responsible for standardization relating to terminals and networks for speech and media quality, end-to-end single media and multimedia transmission performance, Quality of Service (QoS) parameters for networks and services and Quality of Experience (QoE) descriptors and methods.

Our Speech and Multimedia Transmission Quality committee creates and maintains standards relating to speech and end-to-end media quality performance for terminals and networks.

With our Working Group STQ Mobile we liaise with 3GPP, ITU-T and other organizations to support development of specifications for test methods, equipment and performance requirements for use in existing and future network telecommunications services, both fixed and mobile.

In March 2021 the committee published a new Technical Report TR 103 639 that presents a framework for time-slicing KPIs for RTP based speech transmission. This describes measurement methodologies and metrics assessing characteristics of RTP-based speech transmission for fixed duration time intervals. This approach can be used to evaluate aspects of speech transmission based on the observed media volume in terms of time units.

In April STQ Vice Chair Dr.-Ing. Hans Wilhelm Gierlich was recognized as a 2021 ETSI Fellow.

In July the committee’s work on quality of experience in 5G networks – as described in TR 103 559 – was profiled in the ETSI Magazine Enjoy!

In October TC STQ published a revision of TS 103 624, ‘Characterization Methodology and Requirement Specifications for the ETSI LC3plus codec’. This specifies the subjective and objective methodologies developed in cooperation between TC STQ and TC DECT for the characterization of the Low Complexity Communication Codec Plus (LC3plus) speech codec. It also describes experimental tests and conditions used for subjective and objective testing.

Following approval by TC DECT of latest revision of TS 103 634 and its subsequent publication, TC STQ evaluated the performance of the LC3plus (Low Complexity Communication Codec plus), recommending it for global deployment in DECT and VoIP applications.

During the year TC STQ also issued revisions to a number of existing Technical Specifications:

  • TS 103 737 V1.4.1 specifies transmission requirements for narrowband mobile wireless terminals (handset and headset) from a QoS perspective as perceived by the user.
  • TS 103 738 V1.4.1 specifies transmission requirements for narrowband mobile wireless terminals (hands-free) from a QoS perspective as perceived by the user.
  • TS 103 739 V1.4.1 specifies transmission requirements for wideband mobile wireless terminals (handset and headset) from a QoS perspective as perceived by the user.
  • TS 103 740 V1.4.1 specifies transmission requirements for wideband mobile wireless terminals (hands-free) from a QoS perspective as perceived by the user.
  • TS 103 558 V1.3.1 specifies methods, results and analysis of tests for listening effort and listening quality at electrical interfaces of speech communications, taking into account effects of noise and different impairments due to environmental conditions of usage.
  • TS 103 106 V1.6.1 specifies objective testing methodologies for measurement of speech quality for modern mobile terminals in the presence of background noise.

TC STQ also adopted several further work items representing the revision of previously published specifications, with publication expected in 2022:

  • TS 103 607: Transmission requirements for wearable wireless wideband terminals from a QoS perspective as perceived by the user. This will develop methodologies, test arrangements, and requirements for the evaluation of speech communication performance of wideband capable wearable devices from the user perspective.
  • TS 103 814: Speech quality performance in the presence of background noise; Objective test method for terminals in wideband mode. This work will expand upon previous models for the objective prediction of speech quality in the presence of background noise (as specified in ETSI TS 103 106) through the inclusion of new training databases considering modern noise suppression and speech enhancement techniques, device form factors, and usage scenarios.

Work also continued on two items adopted before 2021, which are also expected to attain publication in 2022:

  • TS 103 802: Objective test method for the evaluation of echo impairments. This will provide a test method for the prediction of perception of impairments caused by echo control systems. The prediction is based on the related specification for subjective test procedures (already published as ETSI TS 103 801).
  • TS 103 837: Impact of languages on Listening effort and relationships between listening quality and listening effort. This will analyze the impact on subjective tests results for different languages and will provide the potential consequences for future studies. All subjective tests will be conducted with subjects with typical hearing.

STQ Mobile meanwhile progressed work on three new reports, expected to be published in 2022:

  • TR 103 662: Guidelines for assessing statistical properties of benchmarking and scoring results. This will complement existing published work by proposing additional methods to establish the statistical properties of benchmarking result, such as convergence of QoS parameters, statistical confidence and dependencies on selection of morphological categories.
  • TR 103 703: Recommendations on QoS for emerging 5G use cases in relation to network capabilities. This will describe the structuring and modelling of QoS aspects for typical 5G use cases and how to map them to network capabilities.
  • TR 103 733: Best practices of testing the performance of web content delivery. This will provide recommendations on how to best measure the network performance vs. user experience of downloading modern web content.

See the complete list of TC STQ Work Items currently in development here.