Dual-beam Conformal Hologram Metasurface Leaky Wave Antenna Based On Surface Impedance Modulation

In this paper, a conformal holographic metasurface antenna is investigated for X-band wireless communications. The planar array consists of periodic hexagonal patches with variable sizes. The periodicity controls the direction of the radiated beam through surface impedance modulation. Two tapered microstrip transmission lines are placed at both ends for surface wave launchers. The radiation characteristics of the planar hologram metasurface leaky wave antenna (HMLWA) are investigated. The increase in hexagonal patches cells aperture, increases the radiated gain and radiation efficiency. The peak gain is 20.4 dBi with gain bandwidth of 3 GHz with high efficiency of 87%. The periodicity selection controls the direction and number of radiated beams. Dual-beam at angles $\theta_{1}=32^{\circ}$, and $\theta_{2}=42^{\circ}$ are radiated for two different periodicities $\mathrm{P}_{1}=40$ and $\mathrm{P}_{2}=30$ at operating frequency, f=15 GHz. The effect of curvature on the radiation characteristics of the HLWA is investigated. Two conformal structures, along the longitudinal direction and the transverse direction are explained.