A Single-Layer Miniaturized Self-Decoupled Microstrip Antenna

This paper introduces a novel microstrip patch antenna featuring self-decoupling and reduced size. The antenna design includes two via-shorted microstrip stubs embedded in an I-shaped patch, effectively controlling mutual coupling between antenna elements. This self-decoupling mechanism strategically manages coupling strength in patch-to-patch and stub-to-patch paths, leading to cancellation and improved isolation. A
$1\times 2$
self-decoupled microstrip antenna array is then designed and simulated, with each element sized at
$0.176\times 0.326\lambda _0^{2}$
(where
$\lambda_{0}$
represents the center frequency wavelength in free space). The antenna array achieves isolation exceeding 21.3 dB. Compared to a conventional patch antenna array under the same inter-element distance (
$0.368 \lambda_{0}$
center-to-center), the self-decoupled antenna demonstrates an increase in minimum isolation by 11.3 dB and maximum isolation by 51.4 dB across the -10 dB impedance bandwidth.