Novel Planar Ultra-Wideband Modular Antenna Array with Low Profile

A planar ultra-wideband modular antenna array with an ultra-low profile based on a tight coupling effect is proposed. The antenna array is composed of multi-layer printed circuit boards. Since its frequency operation can extend up to the grading lobe frequency, the number of T/R components for the antenna aperture is reduced to the greatest extent. Specifically, a horizontal fin structure is added on the parallel feeding lines, which assists in improving the impedance matching of the array. In order to break the bandwidth limitation of the low-frequency loop mode, a capacitive short-circuit probe is introduced to push the common-mode resonance point into the low-frequency band. Finally, subject to Active VSWR < 3, the array can realize E-plane, H-plane, and D-plane +/- 45 degrees beam scan coverage across the 6:1 frequency band (3.48-20.97 GHz). A 128-element prototype was processed and tested to validate the design. This array not only has the advantages of low profile, modularity, easy assembly, and maintenance but also minimizes the number of T/R components and reduces the cost of phased array antennas.

Automated summary

This research proposes a planar ultra-wideband modular antenna array with an ultra-low profile based on a tight coupling effect. It improves the performance and bandwidth limitation of the array by adding a fin structure and introducing a capacitive short-circuit probe. The array achieves multi-angle beam scan coverage across a 6:1 frequency band.