Avoiding the downhill [cellular voice quality]
J.P. Conti · Communications Engineer · 2004
A study has been carried out to find out how the voice quality offered by four cellular networks in the USA compared both to each other and to the traditionally high standards attained by the local telephone companies (PSTNs). There was a measurable difference in quality among the different operators, particularly in the downlink section (traffic moving from the PSTN to the wireless user). The second clear finding is that the downlink consistently outperforms the uplink in all networks. This should not come as a major surprise considering that the party regularly paying the operator's bill at the end of each month is the wireless user and not those at the other end of the line. The question of how much worse voice quality really is in the cellular world compared to that of the incumbents also received a resounding answer: a full listening quality MOS (mean opinion score) point when the average overall performance for the four networks is considered (3.3 MOS versus the accepted 4.3 MOS level shown by typical PSTNs). Another interesting discovery was that a mobile phone indicating good signal reception will not necessarily translate into increased voice quality.