Circularly polarized 4 × 8 stacked patch antenna phased array with enhanced bandwidth for commercial drones

This paper demonstrates the design procedure of a 4 × 8 phased array antenna. Initially, a unit element in multilayer topology with orthogonal slots in the ground plane to couple electromagnetic energy is designed. Then, a stacked patch with truncated edges is placed on the top thick substrate layer to enhance the bandwidth to 600 MHz. This multilayered stacked patch unit element is then used to design a 1 × 4 and 4 × 8 slot coupled stacked patch array. On the bottom side, a novel feedline structure is designed to provide a 90 o phase difference at the antenna feed for the circular polarization. The phase difference is achieved in the feedline structure using a quarter wavelength ( λg/4) difference in the lengths. After the numerical validation, both 1 × 4 and 4 × 8 stacked patch antenna arrays are fabricated to validate the simulations. The final 4 × 8 array achieved the target specification of an active reflection of less than −10 dB over 2.4 to 3.0 GHz, axial ratio of less than 3 dB, and stable radiation pattern over the complete band. In addition, beam scanning characteristics of the proposed stacked patch antenna arrays are also verified. The prototype resulted a peak gain of 19.5 dB at 2.7 GHz, 3‐dB beamwidth around 12 o in the xz‐plane, and scanning range of 90 o. Overall, good agreement between measured and simulated results showed that the proposed designed array capable of providing 600 MHz is an excellent candidate for the radar communication, small commercial drones, and synthetic aperture radar applications.