A Dual-Band Dielectric Resonator Antenna With Triple-Mode For Monopole-Like Linear and Circular Polarizations

A dual-band dielectric resonator antenna with triple-mode for monopole-like linear and circular polarizations is proposed. By using a rectangular slot and a central probe, three modes of orthogonality, $TE_{10\frac{1}{2}},TE_{01\frac{1}{2}}$ and $TM_{11\frac{1}{9}}$ mode, can be excited to realize dual-band antenna. It is found that the lower band is composed of the $TM_{11\frac{1}{2}}$ mode with monopole-like linear polarization, while the upper band is formed by the $TE_{10\frac{1}{2}}$ and $TE_{01\frac{1}{2}}$ modes with circular polarization. The impedance bandwidths are 10.38% and 28.7% for the lower and upper band bandwidths respectively. The 3-dB axial-ratio bandwidth is 5.5% for the upper band bandwidth. Meanwhile, a triple-band DRA with triple-mode is proposed.