A Dual-Band Magnetoelectric Monopole Antenna Array Using Mode-Composite Waveguides

A novel substrate-integrated mode-composite waveguide owing two bands where only the quasi-TE
₁₀
mode is supported is presented. The waveguide geometry completely shared in the two bands is equivalent to one transmission channel at low frequencies and a pair of individual channels at high frequencies. With the aid of the waveguide, a dual-band magnetoelectric (ME) monopole array with a relatively large frequency ratio is designed, fabricated, and tested. Benefitting from the shared radiation structure that separately operates as
$1\times2$
and
$1\times4$
arrays in the low- and high-frequency bands, satisfying radiation features are obtained simultaneously in the two bands from 10.3 to 11.7 GHz and from 31.8 to 38.1 GHz. The proposed mode-composite waveguide and antenna array are valuable to emerge dual-band wireless applications operating at both microwave and millimeter-wave frequencies.