IEEE 269A-2012 pdf download IEEE Standard Methods for Measuring Transmission Performance of Analog and Digital Telephone Sets, Handsets, and Headsets
2. Normative references
Insert the following references in alphanumeric order:
ETSI EG 202 396-1, Specch and multimedia Transmission Quality (STQ); Speech quality performance inthe prescncc of background noIsc-Part 1: Background noisc simulation techniquc and background noisedatabase.
ETSI EG 202 396-3, Speech and multimedia Transmission Quality (STQ): Speech Quality performance inthe presence of background noise–Part 3: Background noise transmission–Objective test methods.
ETSI TS 126 132, Universal Mobile Telecommunications System (UMTS): LTE: Speech and videotelephony terminal acoustic test specification (3GPP TS 26.132)
ITU-T Recommendation P.835, Subjective test methodology for evaluating speech communication systemsthat include noise suppression algorithm.
ITU-T Recommendation P863, Perceptual objective listening quality assessmment
Change the following reference:
ITU-T Recommendation P.50, Appendix 1,1998) Test Signals.
3. Definitions
Change the definition of dBm0 as follows:
dBm0: Power levcl in dBm, rclative to a refcrence point called the zero transmission level point, or 0 TLPA signal level of X dBm at the 0is designated X dBm0. In a codec. the 0 TLP is specified inrelationship to the full-scale digital levelor saturation However, digital saturation is generally not 0 dBm0For u-law codecs 0 dBm0 is 3.17 dB below digital full scalc. For A-law codecs 0 dBm0 is 3.14 dB bclowdigital full scale, Far the L16-256 widehand codec, 0 dBm0 is 3.17 dB helow digital full scalc.
4. Test equipment and setup
4.1 Ear simulators
4.1.3 Translation from DRP to ERP
Change 4.1.3 as follows:
Iype 3.3 ear simulator measures at the eardrumn reference point (DRP)
Unless otherwise speeified-or permitted in this-standard, fFor loudness rating calculatjons, measurementscollected at the DR shall be translated to the ERP, This is done because receive and sidetone loudnessrafing specifications are referenced to the ERP lt also permits comparison of measurements made on thevarious type ear simulators.
The choice of translation is generally determined by cither the perlormance specification or the nature ofthe application.
4.1.4 Translation from DRP to free field
Change 4. 1.4 as follows:
Measurements collected at the DRP may be translated to the free field, except for calculating loudnessratings. Some clauses in this standard require translation to the free field. The free field translation may bedone along with the translation to ERP and/or diffuse field. In this case, the free field is defined as soundcoming from 0 degrees azimuth and 0 degrees elevation.
Please see IEEE Std 1652 for the method, translation curves, and background information.
The choice of translation is gencrally determined by either the perlormance specification or the nature ofthe application.
Insert two new subclauses (4.1.5 and 4.1.6) after 4.1.4:
4.1.5 Translation from DRP to diffuse field
Measurements collected at the DRP may be translated to the diffuse field, except for calculating loudnessratings. The diffuse field translation may be done along with the translation to ERP and/or free field.
Please see IEEE Std 1652 for the method, translation curves. and background information.
The choice of translation is generally determined by either the performance specification or the nature ofthe application.
4.1.6 Implementation
For all measurements, the translation from DRP to ERP, or from DRP to a sound field such as DF or FF.may be fulfilled by using a filter as specified in Annex C. A filter shall be used for measurements of peakacoustic pressure,and is recommended for measurements of distortion.
For measurements made with any kind of spectrum analysis, the translation from DRP to ERP may beperformed by using one of the tables in Annex C. Translations from DRP to DF or FF may be performed by
IEEE 269A-2012 pdf download
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