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In this paper, a circularly polarized metasurface antenna for microwave energy harvesting (MEH) is proposed. First, a 4 × 4 metasurface is analyzed and integrated with the microstrip slot based on characteristic mode analysis for broadband, low profile, and high gain metasurface antenna. The measured results show that the impedance bandwidth of the metasurface antenna is 1.82 GHz, the 3 dB axial ratio bandwidth is 0.96 GHz. Subsequently, a wideband rectifier for C‐band is fabricated and measured according complex impedance compression theory. The frequency of efficiency >50% is from 5.1 to 6.3 GHz with 17 dBm input power. Finally, the novel antenna and rectifier are connected as rectenna for MEH, which shows great potential due to the tunability of the polarization mode (right‐handed CP [RHCP]/left‐handed CP [LHCP]) and the flexibility of the structure. [ABSTRACT FROM AUTHOR]

As a representative technique in electronics, the Smith Chart provides a fast, less‐computation, and graphical approach to solve the problems related to impedance matching. In this paper, we transplanted the Smith Chart into the design and analysis of a microwave metamaterial absorber (meta‐absorber) to develop an analytical and graphical approach for impedance matching of electromagnetic wave absorption. Before the structural design, four traces on the Smith Chart plane from the load to arrive at the impedance matching point (the center of the Smith Chart) can be graphically found to obtain perfect absorption. Then, we have designed four impedance matching circuit networks made of resistance, inductance, and capacitive elements and transmission lines to fit the four traces. Then, the matching circuits are mapped into the meta‐absorber structure by using three types of proposed layers. The full simulation method based on the finite element method is used to verify the proposed concept. Furthermore, an external dielectric loading strategy has been developed to achieve good angular stability up to 60° for the radar cross section reduction under transverse electric and transverse mangetic polarization incidence. The proposed method may provide a convenient way for various microwave devices, such as antennas. [ABSTRACT FROM AUTHOR]