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A novel 24 GHz circularly polarised metasurface rectenna for wireless power transmission is designed in this study. Based on experimental measurements and retro‐simulation, an effective approach is proposed to extract the parasitic parameters of a Schottky diode. A highly efficient millimetre wave rectifier with a measured efficiency of 63% is constructed based on the exact equivalent circuit parameters of a diode. A circularly polarised metasurface antenna is adopted as the receiving antenna, and the gain is enhanced by introducing metal vias around the metasurface. The antenna and the rectifier are connected directly via a microstrip line. Measurements show that the metasurface antenna has a gain of 11.3 dBic and an axial ratio of 2.5 dB at 24 GHz. The measured conversion efficiency of the rectenna reaches 63% at 300 Ω load when the input power is 15.2 dBm. The rectenna has the advantages of low profile, which can be conformal to the electrical equipment. [ABSTRACT FROM AUTHOR]

A novel miniaturized wideband antenna based on a hybrid L/T‐shaped metasurface structure is proposed, which is fed by an aperture coupling through a microstrip line. To realize the miniaturization of the metasurface antenna, the hybrid L/T‐shaped metasurface structure composed of several L‐shaped metal patches and T‐shaped metal patches is firstly presented. By placing the L‐ and T‐ shaped metal patches with an inverted arrangement, the capacitances caused by interdigital‐like capacitors can be introduced accordingly, which can decrease the resonance frequency and then realize obvious size reduction. The fabricated antenna prototype exhibits a wide impedance bandwidth of 44.0% (5.93 ~ 9.28 GHz) with reflection coefficient ≤ −10 dB and peak gain of 6.57 dBi within a compact radiation aperture size of 0.32λ0 × 0.39λ0. [ABSTRACT FROM AUTHOR]

A novel wideband low‐profile antenna using a hybrid metasurface (MS) structure is presented. The proposed hybrid MS radiator consists of metal patches of different shapes or arrangements, and is fed by a microstrip line through a coupling slot etched on the ground plane. Several resonance modes can be excited for the hybrid MS radiator when a linearly polarized incident plane wave reaches, while one more resonance mode can be introduced by the coupling slot. As a result, wideband and stable radiation can be obtained. The results of the fabricated antenna prototype indicate a large bandwidth of 57.4% (5.23 ~ 9.44 GHz) and a stable gain with a 2‐dB gain bandwidth of 39.2% in a low profile of 0.09λ0. The performances are demonstrated by both simulated and experimental results. [ABSTRACT FROM AUTHOR]