Pancharatnam–Berry Metasurface-Based Printed Leaky Wave Antenna With Flexible Control of Leaky Wave Radiation

In this paper, a one-dimensional (1D) leaky-wave antenna (LWA) based on Pancharatnam-Berry (PB) metasurface is proposed, which can achieve flexible control of leaky wave with high efficiency. A matching transition is designed to achieve the efficient energy feed from terminal port to PB metasurface. The research reveals that, by designing the phase gradient of PB metasurface, the feeding surface wave can be efficiently converted to radiation wave along the expected direction. In addition, the polarization of radiation wave can be arbitrarily customized by further designing the row phase gradients of PB metasurface. On the other hand, the amplitude of radiation wave can also be controlled by adjusting the polarization conversion ratio (PCR) of PB elements, and thus realizing the sidelobe suppression of far-field radiation pattern. Benefit from the inherent asymmetry of the PB elements and the asymmetrical periodic arrangement, the open-stopband effect of LWA can be eliminated spontaneously. The experimental results verify that the proposed LWA can efficiently radiate at broadside, and can flexibly control the polarization and sidelobe of radiation beam, which provides a flexible way to design LWA with versatile beam control capacity.