A Compact Dipole Antenna for DTV Applications by Utilizing L-Shaped Stub and Coupling Strip

In this study, a small dipole antenna for digital television (DTV) reception band (470-862 MHz) is developed. The antenna is composed of a pair of bent dipoles, which are coupling fed by a coaxial cable. The resultant antenna has compact size of. Two parasitically coupling strips are added to excite one additional resonance mode. Bent dipole antennas and feeding structures are fabricated on the different planes of the substrate to embed two L-shaped stubs, thus resulting in improvement of the impedance matching condition. After careful optimization of the geometrical parameters of the antenna, the resonances are merged and thus, a wide impedance bandwidth is obtained. The measured -6-dB bandwidth of the antenna in free space is 615 MHz (80.4%).