Effects of Packet Loss and Jitter on VoLTE Call Quality

Abstract

This work performs a preliminary, comparative analysis of the end-to-end quality guaranteed by Voice over LTE (VoLTE), examining several millions of VoLTE calls that employ two popular speech audio codecs, namely, Adaptive Multi-Rate (AMR) and Adaptive Multi-Rate WideBand (AMR-WB). To assess call quality, VQmon, an enhanced version of the standardized E-Model, is utilized. The study reveals to what extent AMR-WB based calls are more robust against network impairments than their narrowband counterparts; it further shows that the dependence of call quality on the packet loss rate is approximately exponential when the AMR codec is used, whereas it is nearly linear for the AMR-WB codec.