All four operators in the UK have been supporting Voice over LTE (VoLTE) in their networks since 2018. VoLTE transmits voice calls as data packets over a 4G connection. This way, the otherwise necessary “­circuit-switched fallback“, which forces smartphones to switch back to 3G or 2G in ­order
to take or place a phone call, can be avoided. Also, VoLTE speech codecs ­potentially ­support a wider audio bandwidth providing ­operators with the opportunity to deliver higher speech quality to their customers.

For the voice rating, each drive test car and each walk test team ­carried one Samsung Galaxy S9 smartphone per operator. The phones in the cars called a counterpart in one of the other cars. The phones carried by the walk test teams in the cities and travelling on trains called a stationary counterpart. The connected testing equipment regis­tered the success ratios, call setup ­times and speech quality of the test calls. In ­order to simulate normal smartphone usage, additional data transfers took place in the background of the test calls. As a new KPI in our 2019 setup, we also eva­luate the so-called ­Multi­rab (Multi ­Radio ­Access ­Bearer) Connectivity. This value denominates whether data connectivity is available during the phone calls. The voice scores ­account for 32 percent of the total result.

EE SHOWS THE STRONGEST VOICE RESULTS IN THE DRIVE TESTS IN CITIES, FOLLOWED BY VODAFONE

In the larger cities, EE ­achieves the highest success ­ratios and also the shortest call setup times. On average, EE, Vodafone and O2 show a very good speech quality in this and also all the other considered scenarios, while Three is falling somewhat behind the competition. EE and Vodafone also provide the best Multirab connectivity in all tested scenarios.

VODAFONE AHEAD IN CITY WALK TESTS, FOLLOWED BY EQUALLY STRONG EE AND O2

In the walk tests conducted in the UK‘s larger cities, Vodafone takes the lead, providing the highest success ratios and a 100 percent of Multirab connectivity. EE and O2 follow at a distance and are on par in their overall performance, with EE showing faster call setup times and O2 achieving slightly higher call success ratios. Again, Three scores last in this discipline.

EE TAKES THE LEAD IN THE DRIVE TESTS CONDUCTED IN TOWNS, FOLLOWED CLOSELY BY VODAFONE

In the drive tests conducted in smaller towns, EE again takes the overall lead, but Vodafone follows at a narrow distance. Both contenders offer conveniently short call setup times and comparably high success ratios. The speech quality determined in the towns is slightly better in the EE network.

In this category, Three ­achieves the third rank due to higher success ratios and a slightly better speech quality, while O2 scores last. Both O2 and Three show distinctly longer call setup times in the towns than EE and Vodafone.

EE AND VODAFONE ARE ALIKE IN DRIVE TESTS CONDUCTED ON THE UK ROADS. THREE SLIGHTLY AHEAD OF O2

While travelling on the connecting roads between the cities and towns, the drive test cars determined equally good voice results for EE and Vodafone. EE provides a slightly higher speech quality and shorter setup times in this discipline, while Vodafone shows slightly higher success ratios. As in the towns, Three scores a little higher than O2 also on the roads. Three achieved somewhat higher success ratios, while O2 provides a slightly higher speech quality. Again, the call setup times of Three and O2 are considerably longer than those of EE and Vodafone.

VODAFONE AHEAD IN UK TRAINS, EE RANKS SECOND. THREE AND O2 FOLLOW AT DISTINCT DISTANCE

For the second time in the UK, we have also examined the quality of voice calls conducted in trains. While the results have slightly improved since the previous year, they are still by far weaker than in the other categories. However, ­Vodafone takes a distinct lead when it comes to voice calls on the UK railways, offering still the highest success ratios. EE follows at a distance of almost ten percent of the intermediate r­­esult, while Three and O2 are ­behind with a gap of another ten percent.

DATA

With the volume of transmitted data permanently growing,
data connectivity constantly becomes more important. Which
operator in the UK manages best to meet the increasing demand?

Mobile Operators are constantly striving to provide their customers with the best LTE coverage as well as to deliver the highest data rates. All four UK networks claim to cover a large part of the population with their 4G/LTE services – the claimed percen­­ta­ges range in the high nineties. And all four contenders
are continuing to spend billions on upgrading and expan­ding their networks to meet the increasing demand – including the rollout of their first 5G network cells, However, as the total amount of ­spectrum necessary for commercial 5G deployments was not yet ­available to the operators at the time of ­testing, we have decided to not yet consider this ­mobile network technology in this year‘s umlaut connect Mobile Benchmark in the UK.

In order to assess the performance and reliability of data connections, each of our four drive test cars and also the walk test team ­carried one Samsung ­Galaxy S9 per operator. Supporting the LTE ­category 18, these smartphones are able to ­benefit from the combined use of currently up to five LTE carrier frequencies, “5CA“, as provided in the EE network. Vodafone and O2 widely use “3CA“ in ­urban areas – the combination of three carriers. So practically, the Galaxy S9 can benefit from the “4G+“ ­offerings provided by these operators, which ­currently support up to 1 Gbps download data rates.

umlaut‘s and connect’s testing rewards fast throughputs as well as the networks‘ ­availability and ­stability. In order to assess typical performance as well as peak speeds, we consider two values: the ­minimum data rate that is available in 90 percent of the cases, and additionally the peak data rate that is surpassed in 10 percent of the cases. Web page and file downloads or file ­uploads ­reward fast speeds, while the determina­tion of success ­ratios and ­assessing ­YouTube playouts concentrate on ­reliability ­aspects.

EE LEADS IN DATA DRIVE TESTS, VODAFONE FOLLOWS CLOSELY 

In the drive tests conducted in 21 larger cities, EE leads by a narrow margin, followed by Vodafone. 

O2 achieves a solid third ­position, while Three ranks last. This ­ranking can be seen in most of the data KPIs such as the success ratios and session times of web page ­accesses, the success ratios and transfer speeds of file ­downloads and the success ratios and ­video ­resolutions of YouTube ­playbacks. In terms of data rates, EE and ­Vodafone provide considerably faster speeds compared to O2 and Three in in all aggregations.

VODAFONE AHEAD OF EE IN BIG CITY DATA WALK TESTS

In the overall results of the walk tests conducted in Birmingham, Bradford, Bristol, Cardiff, Glasgow, Leeds, Liverpool, Greater London, Manchester and Sheffield, Vodafone scores ahead of EE with a distinct lead, but both on a high level. O2 ranks third and Three ranks fourth, with both contenders performing weaker than in the ­drive tests. O2 and Three show a clear need for improvement in the ­YouTube tests – which applies to all tested scenarios, but is particularly pronounced in the big city walk tests.

EE AHEAD IN DATA DRIVE TESTS IN SMALLER TOWNS

In the data drive tests that our measurement cars performed in
29 smaller towns, EE takes a clear lead with the highest success ratios and overall good results. The second-ranking Vodafone follows at a considerable distance, while O2 and Three rank closely together and are not too far from Vodafone‘s performance level.

EE LEADS ON CONNECTING ROADS, HIGHER OVERALL PERFOR­MANCE LEVEL ON ROADS THAN IN TOWNS 

On the 6,080 km of connecting roads covered by our test cars, we see the already well-established ranking order: EE scores best, Vodafone follows, succeeded by O2 and Three – each at some distance. Interestingly, the performance level on the roads is overall higher than in the towns.

EE AND VODAFONE AHEAD IN TRAINS – ON AN OVERALL LOW PERFORMANCE LEVEL 

The tests performed in UK‘s  trains reveal a two-tier system: EE and Vodafone perform a little better, O2 and Three considerably weaker. However, the performance level and reliability of data connec­tions on UK‘s railways generally leave much to be desired.