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Glossary

MOS (Mean Opinion Score) in 3GPP: meaning and where it is specified

Published 2026-10-16Updated 2026-10-16

At a glance

Term
MOS
Stands for
Mean Opinion Score
Defined in
3GPP TR 21.905 V19.2.0, clause 4
Used in
TS 26.132, TS 26.247, TS 46.085

In plain words

The vocabulary entry gives MOS as Mean Opinion Score. In TS 26.132, N-MOS-LQO_n abbreviates "Noise (Background) - Mean Opinion Score Listening Quality Objective - Narrowband". TS 46.085 reports statistical analysis and significance tests at 95 % confidence level in terms of Mean Opinion Scores and confidence intervals. TS 26.247 says its model predicts audio-only, video-only, and audio-video MOS on a 5-point Absolute Category Rating scale for operation and maintenance quality monitoring.

Source: 3GPP TS 26.132 V20.0.0, clause 3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/26_series/26.132/26132-k00.zip

Sources

  1. 3GPP TR 21.905 V19.2.0, clause 4. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/21_series/21.905/21905-j20.zip
  2. 3GPP TS 26.132 V20.0.0, clause 3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/26_series/26.132/26132-k00.zip
  3. 3GPP TS 46.085 V19.0.0, clause 7.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/46_series/46.085/46085-j00.zip
  4. 3GPP TS 26.247 V19.1.0, clause K.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/26_series/26.247/26247-j10.zip

How this page was made

The facts box comes straight from the 3GPP TDoc list and specification archive as indexed by 3GPP Scout. An AI model (GPT-6 Luna) wrote the paragraph and named the source of each sentence. Code checked every quote word for word against the stored source text and every number against the cited source. A second AI model from another company (Claude Opus 5.5) reviewed the paragraph against the same sources. The 3GPP documents themselves govern.