3 Abbreviations

3GPP46.008Half rate speechPerformance Characterization of the GSM Half Rate speech codecRelease 17TS

For the purposes of the present document, the following abbreviations apply:

A/D Analogue to Digital

ACR Absolute Category Rating

ANOVA ANalysis Of VAriance

C/I Carrier-to-Interferer ratio

CEPT Conférence Européenne des Postes et Télécommunications

CNI Comfort Noise Insertion

D/A Digital to Analogue

DAT Digital Audio Tape

DCR Degradation Category Rating

DSP Digital Signal Processor

DTMF Dual Tone Multi Frequency

DTX Discontinuous Transmission for power consumption and interference reduction

EID Error Insertion Device

ETSI European Telecommunications Standards Institute

GBER Average gross bit error rate

GSM Global System for Mobile communications

IRS Intermediate Reference System, No IRS= rather flat

HLCS Host Laboratory Control System

ITU-T International Telecommunication Union – Telecommunications Standardization Sector

MNRU Modulated Noise Reference Unit

MOS Mean Opinion Score

MS Mobile Station

OVL Overload point

PCM Pulse Code Modulation

Q Speech-to-speech correlated noise power ratio in dB

qdu quantization distortion unit

RPE-LTP Regular Pulse Excited codec with Long Term Prediction

SCD Signal Conditioning Device

SFC Sending Frequency Characteristic

SID Silence Descriptor

SMG Special Mobile Group

SNR Signal to Noise Ratio

TCH-HS Traffic CHannel Half rate Speech

TDMA Time Division Multiple Access

UPCM Uniform or Linear PCM

VAD Voice Activity Detector

wMOPs Weighted Million OPerations per second

Four different Error Patterns (EP0, EP1, EP2 and EP3) were used, where:

– EP0 without channel errors;

– EP1 C/I=10 dB; 5 % GBER (well inside a cell);

– EP2 C/I= 7 dB; 8 % GBER (at a cell boundary);

– EP3 C/I= 4 dB; 13 % GBER (outside a cell).