A Polarization and Radiation Beam Reconfigurable Integrated Antenna With Broadband and High Gain for mmWave Vehicular Communication

A novel integrated antenna supporting polarization and radiation beam reconfigurability is proposed for emerging millimeter-wave (mmWave) vehicular communication. To meet the reconfigurability requirement of the vehicular communication system, a compact shared-aperture two-dimensional leaky-wave antenna (LWA) is designed. The LWA is generated by the parallel-plate waveguide (PPW) long-slot structure and its open stopband issue is suppressed completely by employing a unit cell with two asymmetrical slots, leading to high-gain and broadband characteristics. Besides, a multifunction feeding network constituted by four switchable input ports, four parabolic reflector systems, and an integrated multifunction coupler is seamlessly incorporated with the radiation aperture within a single substrate, realizing a low-cost solution for vehicular communication applications. Based on the proposed design concept, a broadband high-gain integrated antenna featuring polarization and radiation beam reconfigurability is engineered, fabricated, and installed into an antenna measurement system for validation. Experimental results demonstrate that the proposed antenna achieves a peak gain of 23.6 dBi together with a bandwidth of 56.6% from 19 GHz to 34 GHz. Additionally, it exhibits good polarization and radiation beam reconfigurable capability, providing horizontal/vertical linear-polarization single-beam, right-/left-handed circular-polarization single-beam, and dual-linear-polarization equal/unequal-amplitude dual-beam operating capability. Furthermore, a wide beam scanning coverage of 105$^{\circ }$ in xoz-plane and 108$^{\circ }$ in yoz-plane is achieved by the presented design. The extraordinary advantages of the proposed integrated antenna such as wide bandwidth, high gain, polarization and radiation beam reconfigurability, and low cost make it suitable for various millimeter-wave vehicular communication application scenarios.