3 Definitions, symbols and abbreviations

26.2603GPPObjective test methodologies for the evaluation of immersive audio systemsRelease 18TS

3.1 Definitions

For the purposes of the present document, the terms and definitions given in 3GPP TR 21.905 [1] and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in 3GPP TR 21.905 [1].

spherical coordinates: The coordinate system used in this document is defined such that the x-axis points to the front, the y-axis to the left and the z-axis to the top (see Figure 0). Spherical coordinates are the distance from the origin, the azimuth in mathematical positive orientation (counter-clockwise) and the elevation angle relative to the z-axis (with 0 degrees pointing to the equator and +90 degrees pointing to the North pole).

Figure 0: Spherical coordinate system

dBFS: dB full-scale, where 0 dBFS refers to the RMS level of a DC-free sinusoidal signal exercising the full scale of the digital interface/file.

3.2 Symbols

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

LAeq the sound level in decibels equivalent to the total A-weighted sound energy measured over a stated period of time.

azimuth

elevation

3.3 Abbreviations

For the purposes of the present document, the abbreviations given in 3GPP TR 21.905 [1] 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 [1].