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Abstract-The design of an optimized Wideband ElectronicallySteerable Passive Array Radiator (W-ESPAR) antenna, for Terrestrial Digital Video Broadcasting (DVB-T) reception, is proposed. A genetic algorithm is used in order to calculate the positions and lengths of antenna elements (structural parameters) and loading conditions (control parameters). A nine-element W-ESPAR antenna with one element active and eight passive can have one directive beam per channel, with mean gain of 9 dBi, reflection factor less than 0.2 and input impedance around 75 Ohms. Computer simulations have shown that one main lobe may be achieved in the same direction and for all UHF channels, from 470 MHz to 890 MHz. The analytical results for the design are provided, and they show that the proposed W-ESPAR antenna is suitable for portable DVB-T reception.

The spectral efficiency of the DVB-T protocol in comparison to the analog television systems will inevitably lead to the reduction of the UHF spectrum that is necessary for the current television broadcasts. Even if the number of available TV programs increases, or new services such as High Definition TV (HDTV) are introduced along with DVB-T, there will still be more available spectrum at any given area than today. The spectrum that will be released by most European countries when the full digital switchover is completed in 2012 has been designated as "digital dividend" and is a matter of controversy between broadcasters and mobile communications operators that wish to occupy part of it. This paper examines the coexistence of DVB-T and IMT-2000 mobile telecommunications in the UHF bands IV and V that are used today for television broadcasting on a primary basis. The situation in which both services operate in adjacent (or even in the same) channels is examined on both technical and regulatory grounds, so as to take into account the international standards and rules for television broadcasting and personal mobile communications, as expressed mainly by the International Telecommunications Union (ITU).