A Low-Profile Lightweight Circularly Polarized Rectenna Array Based on Coplanar Waveguide

A low-profile and lightweight circularly polarized (CP) rectenna array based on coplanar waveguide (CPW) is proposed in this letter. The CPW is adopted for enhanced bandwidths. A CPW rectifier, which consists of a matching network, a series diode, and a compact dc-pass filter, is directly integrated on the ground plane of the receiving antenna. The proposed rectenna is fabricated and measured. It features stable conversion efficiencies on three azimuthal planes. The maximum efficiency of 71.2% has been measured with a 400 Ω load at 5.8 GHz. A 4 × 4 rectenna array is also built for a large physical aperture and increased output power. The maximum conversion efficiency of 65.24% is measured with the array. Taking advantage of the immunity to misalignment of the CP receiving antenna, the proposed rectenna and array are suitable to be used in mobile applications for wireless power transmission.