Compact Dual-Polarized Antenna with Low-Pass Response for Marine Communication

Abstract

This paper proposes a compact dual-polarized cross-dipole antenna with low-pass filtering radiation response. The antenna consists of two pairs of orthogonally placed cross-dipoles, a circular patch, a filtering balun and a folded ground plane. Shape of the dipoles and installation of the patch are designed collaboratively to realize wideband and high efficiency in a compact size. The balun, which also contributes a resonance, simultaneously realizes low-pass filtering response at wide stop-band and low loss in passband, with a simple structure. For demonstration, the proposed antenna is implemented. Size of the radiator is 0.28*0.28*0.29 λ <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . The measured 15-dB return-loss bandwidth of the prototype is 32.7%, which covers the 4G bands (from 690 MHz to 960 MHz). In the passband, efficiencies beyond 90% and peak gains of 9.05 ± 0.55 dBi are measured. The half-power beamwidth at passband is maintained 65° ± 5°. At frequencies ranging from 1.7 GHz to 4.0 GHz, the prototype can provide beyond 13 dB gain suppression. The proposed antenna can be a good candidate to integrate with elements operating at higher frequencies to form an aperture-shared array for shore-to-ship communication.