A Dual-Patch Antenna for Easy Arraying With Filtering and In-Band Radiation Pattern Decoupling Properties

A dual-patch antenna with filtering and decoupling properties is introduced. It excites the Quasi-TM<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01</sub> and reverses TM<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">02</sub> modes of the dual patch by loading an open stub on the microstrip feed line, thus introducing radiation zeros at the upper and lower band edges to achieve an effective filtering response. In addition, by combining a pair of vertical slots structures, the antenna provides decoupling effect in the radiation pattern of the same frequency two-element array. Because it has decoupling and filtering characteristics at the same time, it can realize decoupling between units at the same frequency band and adjacent frequency bands simultaneously. Compared with the existing design, thanks to its simple structure and symmetry, it can be more suitable for the layout of multiple antenna elements with the additional advantage of enhanced bandwidth. The measured 10 dB impedance bandwidth for the two-element array in the same frequency band is 6.03% with isolation higher than 14.8 dB, while the two-element array in adjacent frequency bands exhibits −10 dB impedance bandwidths of 6.35% and 7.08% with the isolation higher than 26.1 dB.