Invited Talk: Yu Xiao, Sun Yat-sen University

Special session 24: Advances in Multi-functional Metasurfaces and Applications

Short Bio: 
TBA

Title: Wide-angle Beam-scanning Phased Array Designs Based on the Metasurface

Abstract:
Phased arrays with wide-angle scanning capacity are strong needed in many applications, such as modern wireless communication and radar systems. However, the performance of phased arrays degrades as the beam is scanned off broadside due to the effects of mutual coupling. In this report, wide-angle beam scanning designs based on the metasurface are presented. Two different way to improve the wide-angle scanning performance have been demonstrated by using a same subwavelength cross-shaped metasurface. The first method is using the metasurface layer as the wide-angle impedance matching (WAIM) layer and loading it above the antenna array to improve the impedance matching with free space. A 16 × 16 reconfigurable transmitarray antenna has been designed to verify this design. The scan loss in the H-plane has been improved by 2 dB. The scan loss at 60◦ are better than 4 dB in both the E-plane and the H-plane. The second method is using the metasurface layer as a decoupling wall between adjacent elements. It will lead an energy cancellation with proper parameters. Two perpendicular linear arrays have also been fabricated to verify the design. The measured 3-dB beam width of the active element pattern (AEP, in the array environment) with the integrated metasurface is about 150°in the E-plane and 109°in the H-plane. The measured 3-dB gain fluctuation of the scanned beam is from -78°to 78° in the E-plane array and from -69°to 69° for the H-plane.