In 4th quarter 2015, the digital terrestrial television (DTT) signal in Portugal was reported as providing service availability values of close to 100% and high levels of service stability; this according to a study conducted by ANACOM based on the information obtained from the national network of probes. Overall, it can be affirmed that, in areas of the country where the digital television signal is provided terrestrially through channel 56, television reception was provided almost entirely on a constant and uninterrupted basis.
Viana do Castelo, with the highest level of reception availability (99.98% availability), Portalegre (99.96% availability) and Guarda (99.95% availability) were the districts with the highest levels of availability.
Aveiro (97.8% availability) and Setúbal (99.5% availability) were the districts reporting the lowest results, with all other districts performing above the national average (99.66% availability).
In terms of daily levels of service availability, 7 December was the best day and 2 October the worst with 99.96% and 98.24% availability, respectively.
Of the quarter’s three months, December was the one in which the DTT network performed best, with service availability of 99.70%, while October saw the lowest level of service availability (99.62%).
It should be noted that interruptions in access to the service may be due to power failures, bad weather, self-interference and vandalism of infrastructure.
As regards service stability, 4th quarter 2015 was characterized as a period in which service stability was high (compared to average signal quality, the variations were not likely to create any difficulty in DTT reception).
The months with the highest and lowest service stability were December and November respectively. The days with highest and lowest levels of stability were 20 December and 2 October, respectively. Nevertheless, even when the signal is less stable, the majority of users may still not notice any change and only those who have poor condition installations and poor equipment quality would notice a degradation.
Throughout the quarter, the time of day when, on average, the network was most stable for DTT signal reception was between 1.00 pm and 2.00 pm whereas the worst time of day, albeit with high service stability, was between 21:00 and 22:00.
The study, available at http://www.mce-anacom.pt/tdt/sondas_relatorio.phphttp://www.mce-anacom.pt/tdt/sondas_relatorio.php, was completed using over 15 billion data readings obtained from the probe network and focuses only on the television signal broadcast on channel 56. However, currently the signal is also broadcast using channels 40, 42, 45, 46, 47, 48 and 49.
