Spiral and Multimode Antenna Miniaturization for DTV Signal Receptions

In this letter, a novel broadband miniaturized antenna is presented. This antenna is proposed for operation in the digital television (DTV) reception band (470-862 MHz) throughout the world. This antenna uses a 50- microstrip line to feed. To achieve broadband characteristics, the proposed antenna is constructed using seven resonance paths in the ground plane. For compact structuring, a signal line is used in the proposed antenna, while ground plane coupling is used to induce the capacitance effect. The impedance matching and bandwidth of the proposed antenna are significantly affected by the sheet metal on the signal line. The antenna is able to realize an omnidirectional radiation pattern over the entire frequency band. Furthermore, the measurement results agree with the simulation ones.