Downlink Capacity of UMTS Coexisting with DVB-T MFNs and Regional SFNs

The downlink capacity of a UMTS Terrestrial Radio Access Network (UTRAN) sharing the frequency spectrum with a terrestrial digital video broadcasting (DVB-T) network is investigated in this paper. For the DVB-T network, rooftop and portable outdoor reception is considered, for both, Multi Frequency Networks and regional Single Frequency Networks. The necessity to limit the interference between UTRAN and DVB-T renders the channels of the DVB-T transmitters closest to a UTRAN cell unusable for this cell. For the same reason, the transmit power per (usable) UTRAN carrier needs to be restricted, thus limiting the capacity per carrier. Allowing a DVB-T outage increase from 5% to 6%, the UTRAN capacity is still close to 100% of that of a non-coexisting UTRAN for cells of radius smaller than 2.5km. Since not all channels are usable in every cell, the total capacity per cell is smaller than in non coexistence, for the same spectrum range available to UTRAN. The relative total capacity is still 34%. This somewhat smaller total capacity is compensated by the huge DVB-T frequency range of up to 400MHz that could be exploited for coexistence.