Design of Dual-/Wide-Band Quasi-Yagi Antenna Based on a Dielectric Resonator

This paper presents a design approach of dual-/wide-band quasi-Yagi antenna using a dielectric resonator (DR). A single rectangular DR operating at TE
_1δ1
and TE
_1δ3
modes can be differentially fed by the coplanar strip line (CPS) and then is used as a driver, which functions as a dual-mode magnetic dipole (M-dipole) resulting from the TE
_1δ1
and TE
_1δ3
modes. Thus, a dual-band quasi-Yagi antenna with two close operation frequencies can be designed, meanwhile, the two bands can be independently controlled. Based on this, a wide-band quasi-Yagi antenna is introduced by adding two metal directors with different sizes on the top and bottom layers of the supporting substrate. The two directors provide two additional resonant frequencies, turning dual-band antenna into a wide-band one. To verify the design concepts, two prototypes of dual- and wide-band antennas are fabricated and measured. Good agreement between the simulated and measured results can be observed. The wide-band antenna has a measured -10 dB impedance bandwidth of 21.7 % (9.33 - 11.6 GHz). Within it, the peak gain of antenna is 8 dBi and 1 dB gain bandwidth is 15.5%.