Wideband and Wide-Angle Scanning Patch Array Antenna With Substrate Cavity and Parasitic Layer Integration

This paper presents an 8×8 planar phased array antenna with wideband, wide-angle scanning ability and a simple structure for C-band applications. The proposed design incorporates a miniaturized cavity-embedded substrate (12×12 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>) for enhanced impedance bandwidth and a parasitic patch-matching layer positioned 4 mm above the lower patch for optimized scanning performance. The primary radiating patch is directly fed with ground via a coaxial probe, while the upper patch is magnetically coupled. The array achieves a bandwidth of 61.81% (3.8–7.2 GHz) in the E-plane and an overlapped bandwidth of 44% (4.6-7.2 GHz) for both E & H-planes. Experimental results demonstrate exceptional beam-steering performance, with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula>60°coverage in both E and H-planes. Meanwhile, the active voltage standing wave ratio (VSWRs) is experimentally validated to be <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\le$</tex-math></inline-formula> 3, with the simulated (VSWRs) values remaining <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\le$</tex-math></inline-formula> 3.4, ensuring effective impedance matching throughout the scanning range. A fabricated 64-element prototype exhibits excellent agreement between measured results and full-wave simulations. The overall design demonstrates mechanical simplicity, broadband performance, and strong angular stability, making it a promising candidate for modern radar and wireless communication integration