3 Definitions, symbols and abbreviations
26.1323GPPRelease 18Speech and video telephony terminal acoustic test specificationTS
3.1 Definitions
For the purposes of the present document the terms narrowband, wideband, super-wideband and fullband refer to signals associated with the corresponding operating modes of the speech codecs specified in 5.2.
For the purposes of the present document, the terms dB, dBr, dBm0, dBm0p and dBA, shall be interpreted as defined in ITU-T Recommendation G.100 [51]; the term dBPa shall be interpreted as the sound pressure level relative to 1 pascal expressed in dB (0 dBPa is equivalent to 94 dB SPL).
A 3GPP softphone is a telephony system running on a general purpose computer or PDA complying with the 3GPP terminal acoustic requirements (TS 26.131[1] and 26.132).
For the purposes of the present document the term clock skew is defined as the difference between the clock of the device under test (CDUT) and the clock of the reference client (CREF). The skew of CDUT relative to CREF is defined in parts per million (PPM) as: (CDUT -CREF).106/ CREF.
For the purposes of the present document, the term electrical interface is defined as an analogue or digital access to an UE, which allows injecting and capturing signals electrically instead of through an acoustical interface. The interface can be either wired (analogue, digital) or wireless (digital). The purpose of this interface is to connect a separate device (typically a headset), which provides a receiver and transmitter for telephony.
For the purposes of the present document, the term traditional earpiece is defined as an acoustics outlet designed to be positioned at or near the ERP.
3.2 Abbreviations
For the purposes of the present document, the abbreviations given in 3GPP TR 21.905 [47] and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in 3GPP TR 21.905 [47].
5GC 5G Core Network
ADC Analogue to Digital Converter
AMR Adaptive Multi Rate
CSS Composite Source Signal
DAC Digital to Analogue Converter
DRP Eardrum Reference Point
DTX Discontinuous Transmission
ECRP Ear Cap Reference Point
EEC Electrical Echo Control
EEP Ear Entrance Point
EL Echo Loss
ERP Ear Reference Point
EVS Enhanced Voice Services
FFT Fast Fourier Transform
G-MOS-LQOn Global (Overall) – Mean Opinion Score – Listening Quality Objective – Narrowband
G-MOS-LQOw Global (Overall) – Mean Opinion Score – Listening Quality Objective – Wideband
G-MOS-LQOfb Global (Overall) – Mean Opinion Score – Listening Quality Objective – Fullband
HATS Head and Torso Simulator
IMS IP Multimedia Subsystem
LSTR Listener Sidetone Rating
LTE Long Term Evolution
MECRP Manufacturer Ear Cap Reference Point
MRP Mouth Reference Point
MS Mobile Station
MTSI Multimedia Telephony Service for IMS
N-MOS-LQOn Noise (Background) – Mean Opinion Score Listening Quality Objective – Narrowband
N-MOS-LQOw Noise (Background) – Mean Opinion Score Listening Quality Objective – Wideband
N-MOS-LQOfb Noise (Background) – Mean Opinion Score Listening Quality Objective – Fullband
NR New Radio
OLR Overall Loudness Rating
PCM Pulse Code Modulation
PDA Personal Digital Assistant
POI Point of Interconnection (with PSTN)
PSTN Public Switched Telephone Network
RP Reference point (electrical or acoustical)
RLR Receive Loudness Rating
RMC Reference Measurement Channel
RMS Root Mean Squared
SLR Send Loudness Rating
S-MOS-LQOn Speech Signal Quality – Mean Opinion Score – Listening Quality Objective – Narrowband
S-MOS-LQOw Speech Signal Quality – Mean Opinion Score – Listening Quality Objective – Wideband
S-MOS-LQOfb Speech Signal Quality – Mean Opinion Score – Listening Quality Objective – Fullband
SS System Simulator
STMR Sidetone Masking Rating
SS System Simulator
TX Transmission
TCL Terminal coupling loss
TCLw Terminal coupling loss (weighted)
USB Universal Serial Bus
USB-C USB Type-C connector/socket
UE User Equipment
UMTS Universal Mobile Telecommunications System
WLAN Wireless Local Area Network