Wideband and Dual-Polarized Crossed Dipole Antenna Design Using Substrate-Integrated Coax

Abstract

A wideband and dual-polarized dipole antenna design technique is presented. The proposed antenna employs two sets of dipole elements in orthogonal configuration and separated by a dielectric layer. The dipole elements are excited with two separate substrate-integrated-coaxial feeds to achieve high port-to-port isolation and the overall antenna stackup is enclosed in a substrate-integrated-waveguide (SIW) cavity. To validate the proposed substrate-integrated-coaxial fed dual-polarized antenna design method, a prototype antenna was fabricated using standard multi-layer printed circuit board (PCB) manufacturing technologies to operate in the Ku-band. Measured and simulated results exhibit that the designed antenna has a wide impedance bandwidth of less than -10dB reflection coefficients at 10.28-14.8GHz and the port-to-port isolation between the two orthogonally polarized dipole antenna ports is greater than 20dB at most frequencies, making it suitable for many applications such as satellite communications. The antenna has a relatively stable gain pattern with a gain value of 5.5-6.5dBi and a low cross-polarization level (lower than 16dB) over the operating frequency range.

Keywords

• Dual-polarization
• wide bandwidth
• high port-to-port isolation
• low cross-polarization
• substrate-integrated-waveguide (SIW)
• printed circuit board (PCB) antennas