Behind the VoLTE Curtain, Part 5

Behind the VoLTE Curtain, Part 5

Stress Testing EVS and AMR-WB in a Top-Secret Laboratory

06/07/2016 | 43 pages
Price: $1,025.00

In this Signals Ahead report we continue our multi-part series on VoLTE-related topics by providing the results of the industry’s first lab-based independent benchmark study of the EVS voice codec and how it compares with AMR. This study is part one of a two-party study with the second study taking place in an LTE network with commercially-launched EVS services.

Highlights of the Study include the following:

Our Thanks.  Consistent with all of our VoLTE-related studies, this report was done in collaboration with Spirent Communications who provided its test platform and engineering resources to conduct the tests. SRG takes full responsibility for the analysis and opinions presented in this report.

The Devices.  We tested two commercial smartphones – the LG G5 and the Galaxy S7 Edge, which were also designed to allow us to configure them to support the various codecs and bit rates. We also tested a Qualcomm MTP as part of the study.

The Scope.  We tested AMR-NB, AMR-WB, EVS-NB, EVS-WB and EVS-SWB, including with Channel Aware Mode (CAM). We also included a large range of bit rates for the two codecs, all subject to the capabilities of the devices we tested.

The Results.  The results of our study indicate that EVS delivers on its promises – better voice quality than AMR and/or comparable voice quality while using fewer network resources, plus EVS is more impervious to IP impairments. However, the performance advantages are more nuanced than we had anticipated.

EVS versus AMR, Part II.  In part two of our study, due out in July, we’ll look at how EVS compares with AMR in a commercial network. We’ll look at multi-mode operation, including EVS to AMR and EVS to VoWi-Fi calls, and include additional KPIs, such as network resource requirements and current consumption.