Coupling-offset path branch and high-isolation millimeter-wave phased array antenna based on the same

A high-isolation millimeter-wave phased array antenna, comprising a plurality of radiating stacked microstrip patch elements, a shielding metal wall, several coupling-offset path branches, a metal ground plane, a feeding network layer, a first port, and a second port;

• wherein each of the coupling-offset path branches comprises two or more first grounded vias and at least one metal strip;
• when the at least one metal strip is one metal strip, the coupling-offset path branch is composed of the two first grounded vias and the metal strip, the two first grounded vias are symmetrically placed along a center of the metal strip;
• and when the at least one metal strip comprises a plurality of metal strips, the coupling-offset path branch is composed of the plurality of first grounded vias and the plurality of metal strips, every two of the first grounded vias are symmetrically placed along a center of one of the metal strips, and the plurality of metal strips are placed in parallel;
• the radiating stacked microstrip patch elements are located on an uppermost layer, the coupling-offset path branches are located between the radiating stacked microstrip patch elements, the feeding network layer is located on a lowermost layer, the metal ground plane is arranged between the radiating stacked microstrip patch elements and the feeding network layer, and an I-shaped slot is etched in the metal ground plane;
• the first port and the second port are respectively located on a center line of a corresponding radiating stacked microstrip patch element of the radiating stacked microstrip patch elements;
• the first port is excited, energy of the feeding network layer is coupled to the corresponding radiating stacked microstrip patch element through the I-shaped slot, and the energy is transmitted to the second port adjacent to the first port through an inherent coupling path portion;
• and the coupling-offset path branches are introduced to offset the inherent coupling path, thus achieving a high-isolation effect between the first port and the second port.