A copper strip and conductive paint-based low profile stripped helical antenna for circular polarization over wide axial-ratio (AR) bandwidth are presented. Impacts of strip widths and geometric parameters of the helix on antenna performance (impedance bandwidth, reflection coefficient, AR, gain) are analyzed thoroughly. In terms of performance parameters, the proposed design is also compared with traditional designs of wire and strip-based helical antennas. Proper impedance matching in the proposed design is achieved by the non-conformal placement of the strip. For easing the fabrication complexity, the antenna is again simulated with a dielectric-based supportive structure, and the impact of this additional support is discussed. The antenna is then constructed on a 3D printed polylactic acid (PLA) based structure. Finally, the 1.3-turn strip-based helical antenna with a radius of 18 mm provided impedance and 3-dB AR bandwidths of 99% and 82.52%, respectively. The maximum gain of 9.40 dBi was found at 2.05 GHz in 3-dB AR bandwidth. The height of the presented antenna is 0.35 λ 0 , where λ 0 is the free space wavelength at the frequency of 2.65 GHz. Low profile and wide AR bandwidth facilitate the use of this antenna in space communication.

A semiellipsoidal helical antenna (SEHA) is formed by scaling a hemispherical antenna in the axial direction. Effects of scaling factors on reflection coefficient (S11), axial ratio bandwidth (AR BW), and gains were analyzed thoroughly. By considering the best scaling factor, analysis is continued for strip‐based SEHA. It is observed that keeping the strip face parallel to the ground plane eliminates the concern of extra impedance matching issues and improves the overall performance over its wire‐based counterpart. For prototyping, the antenna is constructed independently on polylactic acid and acrylonitrile butadiene styrene plastic‐based supportive structures. Simulated and measured results are well agreed upon. When the height (h) in the axial direction is twice the hemispherical radius (r), the antenna provided maximum impedance and 3‐dB AR bandwidths of 144% and 77.53%, respectively, with a maximum gain of 8.83 dBi. The proposed antenna would be a good contestant in satellite communication where a broadband circularly polarized antenna is required.

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