1 Scope

26.4533GPPCodec for Enhanced Voice Services (EVS)Release 17Speech codec frame structureTS

The Enhanced Voice Services (EVS) Codec is specified in the series of Technical Specifications TS 26.441 [3], TS 26.442 [4], TS 26.443 [5], TS 26.444 [6], TS 26.445 [7], TS 26.446 [8], TS 26.447 [9], TS 26.448 [10], TS 26.449 [11], TS 26.450 [12], TS 26.451 [13] and TS 26.452 [15]. The EVS Codec is characterized in TR 26.952 [14].

The present document describes the "generic frame format" for the EVS Codec for the application in 3G Circuit-Switched Networks. This format is based on the RTP framing, as specified in TS 26.445 [7]. This generic frame format will be used as a common reference point, when interfacing speech frames between different elements of the 3G system. Appropriate mappings to and from this generic frame format will be used within and between each system element.