Radiation characteristics of on-glass mobile antennas for digital terrestrial television

Digital terrestrial television (DTV) services began in Japan in December 2003. At present, monopole antennas are used for mobile reception of TV signals, despite suffering some severe problems. Monopole antennas protruding from a car body are easily broken and spoil the appearance of a car. The main lobe of a monopole installed on a car is above the horizontal plane, but the angle of incidence of the TV signal is almost horizontal, so poor reception quality results. Thus, monopole antennas do not meet the stringent requirements of mobile DTV reception. We have developed a novel horizontally polarized on-glass antenna which is suitable for DTV reception, because its elevation pattern peak is horizontal when installed on a car. Other merits are broad input impedance bandwidth across the UHF band (470-770 MHz), and not spoiling the appearance of a car.