In October and November 2008, ANACOM - Autoridade Nacional de Comunicações carried out an evaluation of the quality of the mobile voice services (GSM), video telephony (UMTS) and network coverage (GSM and WCDMA) provided by the operators OPTIMUS, TMN and VODAFONE in major urban areas and along the main roads of Mainland Portugal. The evaluation was made through the analysis of technical parameters that reflect the perception of quality from a consumer point of view. The study concludes that as far as GSM systems are concerned the situation is good, without significant differences between urban areas and main roads or between operators. However this is not the case with UMTS (3G) where differences were found, both between operators and between the quality levels recorded in urban centres and along roads. Furthermore, these levels were significantly lower due to the existence of areas with poor or no WCDMA coverage.
The study examined the main quality indicators from a user perspective of the user and the services examined: network coverage; service accessibility; call connection times; call termination rates; call audio quality; and call video quality.
The results recorded for the quality of service indicators evaluated in this study show good levels of signal coverage for GSM mobile communications systems (99.78% for TMN, 99.67% for Optimus and 99.5% for Vodafone) and good levels of performance for the voice service, both in urban areas and along main roads. No significant difference were found between operators and the levels of coverage remain in line with those found in the previous study.
The performance of the UMTS systems is inferior to that of GSM, but has shown considerable positive development since the ANACOM included these systems in their analysis (in November / December 2006). However, there remain significant differences between urban areas and main roads - in urban areas the systems have good levels of performance, with coverage rates reaching 98.6% in the case of Optimus and Vodafone; and 96.7% in the case of TMN. The capability for establishing and maintaining video telephony calls is 97.3% for Vodafone, which registered the best performance; TMN registered a rate of 96.1%, while Optimus came in with the lowest value, 95.5% - values which reflect a marked improvement over the previous year.
With respect to the indicator on call termination rates, there are no significant differences between operators, with performance levels exceeding 98.2%.
Meanwhile, along main roads it was found that the level of performance of the video telephony service remains inadequate, a direct result of there being areas with poor or inexistent WCDMA coverage. Optimus was found to have the best levels of coverage with 89.86%, followed by TMN with 88.1%, and Vodafone at 79.6%.
For the indicator that measures the call establishment success rate, TMN performed best with a success rate of 92.1%, followed by Optimus with 87.2%, and finally Vodafone with 80.1 %. Compared to the 2007 study, there are very significant improvements in this indicator along the roads: 17.04% for the Optimus, 9.84% for TMN, and 8.61% for Vodafone.
For the indicator measuring the Call Termination along the roads, the best performance was achieved by Optimus, with 96.5% of calls terminating normally, followed by TMN, with 94.9%; and Vodafone with the poorest performance at 92.1%.
The Average Call Establishment Time does not show significant differences between urban areas and roads, and the best average time recorded was for Vodafone, with 5.4 seconds, while TMN was the longest at 7.6 seconds.
The measurements for this study were taken on weekdays and during normal working hours, from 6 October to 11 November 2008. 23,688 test calls were made and 4,708,610 measurements taken of the radio signal, which corresponds to approximately 218 hours of measurements over 9,750 kilometres.
The breadth of sample used means that the maximum margins of error for the overall results obtained for each operator are below 1% in urban areas, and less than 2.53% along the roads, with confidence level of 95%.
NOKIA N95 and NOKIA 6680 terminal equipment was used, and the tests were carried out using moving vehicles with external antennas; the length of calls, both in voice and in video-telephony was 120 seconds.