All four operators in the UK now support Voice over LTE (VoLTE). 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 in order to take or place a phone call, can be avoided. Also, VoLTE supports better audio codecs providing operators with the opportunity to deliver higher speech quality to their customers. For the voice rating, each drivetest car and each walktest team carried one Samsung Galaxy S8 smartphone per operator. The phones in the cars called a counterpart in one of the other cars. The phones carried by the walktest teams called a stationary counterpart. The connected testing equipment registered success ratios, call setup times and speech quality. In order to simulate normal smartphone usage, data transfers took place in the background of the test calls.

EE AHEAD IN BIG CITY WALKTESTS
The walktest teams generally captured a higher performance level for voice in the cities than the drive­test teams – except for O2 which reaches a degree of fullfillment of 75 per cent in both disciplines. EE shows an impressive success ratio of 100 per cent and also very good results for the other KPIs. The ranking is the same as in the drivetests. O2 offers nice speech quality, but lags behind in the other KPIs.

EE HAS ALSO BEST RESULTS IN TOWNS
The results of the drivetests leading through 35 towns accounts for the same ranking as in the cities. EE is leading once again, followed by Vodafone, and Three is close behind. O2 ranks last. Interestingly, Three and O2 achieve slightly better results in the smaller towns than in the big cities. Also, it is pleasing to see that the performance of all four candidates in the towns went up compared to the previous year.

EE STREETS AHEAD ON ROADS 
When it comes to conducting voice calls on the roads, EE is again in the lead. Vodafone ranks recond, with Three and O2 following at some distance. Again, compared to last year’s results, all four UK operators managed to increase their performance in this discipline. With call success ratios aorund 97 per cent, even the weaker contenders offer an acceptable level of voice service.

EE LEADS IN OVERALL WEAK
RESULTS ON BRITISH RAILWAYS
For the first time in the UK, this year’s P3 connect Mobile Benchmark also comprises walktests conducted while travelling on British trains. However, their results are quite sobering: Even EE as the strongest candidate only achieves 48 per cent of the possible points in this discipline. Vodafone follows with a meagre 29, Three at 27 and O2 at 24 per cent. The main problem is the very limited call success ratios – our tests results indicate that EE customers only stand a 87 per cent to get through when trying to conduct a phone call while travelling on a British train. This chance drops to 81 per cent in Three’s and O2’s networks and to even 78 per cent at Vodafone. The latter at least offers better call setup times when such a call attempt actually succeeds.

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?

Data connectivity is the most prestigious discipline in our benchmark and also in the operators’ marketing. All four UK networks claim to cover a large part of the population with LTE services – the claimed percentages range in the high nineties. Three states a combined 3G/4G data coverage of 99 per cent of the population and specifies that about 84 per cent of its 10.1 million customers are using 4G (also see page 3). All four operators are continuing to spend millions and billions on upgrading and expanding their networks to meet the growing demand. However, the four operators pursue different rollout strategies. EE and Vodafone chase each other with continually growing data rates that currently go up to 1 Gbps, based on the so-called carrier aggregation (the combination of multiple carrier frequencies). In contrast, O2 and Three stick around a solid 100 Mbps and mainly focus on enlarging their 4G footprints.

P3’S SCORING REWARDS HIGH PERFORMANCE AS WELL AS THE NETWORKS’ AVAILABILITY AND STABILITY
In order to assess the performance and reliability of data connections, each of our four drivetest cars and also the walktest team carried one Samsung Galaxy S8 per operator. Supporting the LTE category 16, these smartphones were able to benefit from carrier aggregation up to 1 Gbps. P3‘s testing considers such fast throughputs as well as the networks‘ availability and stability. The benchmarking of webpage downloads as well as file downloads and uploads rewards fast throughputs. At the same time, P3 assesses the networks‘ availabilty and stability by examining success ratios. In order to assess typical performance as well as peak speeds, we determined the minimum data rates that are availability in 90 per cent of the cases plus the peak data rates that would be surpassed in 10 per cent of the cases.

YouTube playouts concentrate on reliability aspects. As YouTube streams videos at adaptive bitrates, the average value of the received video resolution is another important performance indicator.

EE TAKES THE LEAD IN CITY DRIVETESTS
In the scoring of their performances determined during the drivetests conducted in 22 UK cities, EE takes the lead, followed by a strong performance by Vodafone. These two operators overall deliver quite high success ratios, convincing download speeds and Youtube playback performance. O2 and Three fall behind, with O2 scoring slightly better than Three in this category.

EE AND VODAFONE ON A PAR  IN BIG CITY WALKTESTS
In the data results of the walktests that were conducted in ten large cities of the UK, EE and Vodafone achieve the same score. Looking closer at the single KPIs, both are on a par in the web tests, EE is a little ahead in the file transfer tests and Vodafone lead regarding Youtube playback. The gap between the leading duo and the other contenders is a little more pronounced, with O2 falling behind distinctly in this category. Among other weak points, O2 shows noticeably low success ratios when it comes to playing back Youtube videos. In terms of using data connectivity while walking in the big cities, there is clearly a two-tier system in the UK.

THREE IS DATA CHAMPION IN TOWNS
Providing data connectivity in towns seems to be the domain of Three. Here the smallest UK operator even outperforms the strong contenders EE and Vodafone. O2 ranks last, offering the same overall performance as in the larger cities. 

EE RANKS FIRST ON THE ROADS, BUT GOOD RESULTS FOR ALL CONTENDERS
The scores achieved by the UK operators on the connecting roads is altogether pleasant. EE leads, but the other three contenders show also good results. More good news: All four operators show better data performances on the roads compared to their results from last year.

EE BEST ON RAILWAYS,
BUT OVERALL MUCH ROOM FOR IMPROVEMENT
While there is good news concerning data performance on the roads, the same can unfortunately not be said about the railways. Only EE shows relatively acceptable performance in this discipline. Three ranks second, Vodafone third and O2 last – each at a distinct distance to their competitors.