Wideband Printed Antipodal Vivaldi Antenna using Straight Slots for UHF DVB-T/T2 Applications

This paper presents a wideband printed antipodal Vivaldi antenna using straight slots for UHF DVB-T/T2 applications covering a frequency range of 470–862 MHz. The proposed antenna consists of two radiation flares with straight slots and a feeding line. A wideband impedance matching was achieved by inserting the slots between the flares and the feeding line. For the experimental verification of the proposed antenna, it was fabricated on a flat circular printed circuit board (PCB) substrate with a radius of 0.25 λ0, where λ0 is the wavelength at 0.74 GHz (the center frequency of the operating band). The measured −10 dB impedance bandwidth and maximum gain were approximately 72.1% (0.47–1.00 GHz) and 2.57 dBi, respectively. Due to the addition of the slots, the impedance bandwidth of the proposed antenna was improved by approximately 212% compared with the Vivaldi antenna without slots.