A Novel Vector Synthetic Dipole Antenna and Its Common Aperture Array
A novel vector synthetic dipole (VSD) antenna is first demonstrated in this communication. Its structure is very simple. The antenna consists of a reflector, four aluminum plates, and a feeding substrate. It can provide a wide bandwidth from 690 to 960 MHz when <inline-formula> <tex-math notation="LaTeX">$\vert \text{S}_{11}\vert < -14$ </tex-math></inline-formula> dB or VSWR < 1.5. The antenna size is only <inline-formula> <tex-math notation="LaTeX">$118 \times 118\times 78$ </tex-math></inline-formula> mm<sup>3</sup>, far less than the size of the similar antennas. Extremely high port isolation and low cross polarization are obtained due to the adoption of the vector synthesis technique. Then, an upper band element is put into the cavity formed by the lower band VSD element, realizing common aperture. Another upper band element is settled next to them with a certain distance, making the whole structure easy to be extended to an array. By using reasonable phase compensation, this hybrid antenna can obtain a good radiation pattern. To further verify the design, an array that consists of two lower band elements and four upper band elements is manufactured and tested. The proposed antenna has the merits of compact size, wide bandwidth, high isolation, and good radiation performance. It will find wide application in the current and future communication systems.