This paper discusses the miniaturization process and bandwidth enhancement of circularly polarized (CP) antenna using asymmetric coplanar strip (ACS) feeding. The antenna mainly uses an ACS feeding scheme on which a via-less composite right/left-handed (CRLH) transmission line (TL) inspired unit cell is implemented for antenna miniaturization and a rectangular shaped annular ring slot is introduced in the asymmetric ground plane (AGP) for generating extended CP radiation. Due to this, the intended antenna offers a compact electrical size of 0.22 λ₀ × 0.35 λ₀ × 0.028 λ₀ at 5.5 GHz and a smaller physical dimension of 12 mm × 19.5 mm × 1.52 mm with ka = 1.32. The novelty of the antenna is to generate an improved impedance bandwidth (IBW) of (5.33–5.86 GHz) 9.90%, and enhanced axial ratio bandwidth (ARBW) of (5.33–5.79 GHz) 8.27% with less design complexity. The intended CP antenna provides a measured gain of 2.43 dBic at 5.53 GHz and radiation efficiency better than 87% is obtained by maintaining the antenna compactness without the use of complicated vias. Also, the intended antenna provides a good AR beamwidth of 80° (+40° to -40°) and positive gain values for theta = ±36° and for all phi values (phi = 0⁰–360°) at 5.55 GHz. Moreover, the intended antenna provides 42.85% miniaturization compared to a conventional monopole antenna. Hence, the intended antenna is well suited for the 5.80 GHz WLAN (5.725–5.875 GHz), and 5.5 GHz WiMAX (5.25–5.85 GHz) applications.

本文讨论了使用非对称共面带（ACS）馈电的圆极化（CP）天线的小型化过程和带宽增强。天线主要使用ACS馈电方案，在该方案上，实现了无孔复合右/左手（CRLH）传输线（TL）激励的单元，以实现天线的小型化，并在不对称接地平面中引入了矩形环形圈槽（AGP）用于生成扩展CP辐射。由于这个原因，预期的天线提供的0.22λ的紧凑电尺寸₀  ×0.35λ ₀  ×0.028λ ₀在5.5GHz和12毫米×19.5毫米较小的物理尺寸×1.52毫米与か = 1.32。天线的新颖之处在于可以产生（5.33-5.86 GHz）9.90％的改进的阻抗带宽（IBW），以及（5.33-5.79 GHz）8.27％的增强的轴向比率带宽（ARBW），且设计复杂度更低。预期的CP天线在5.53 GHz时可提供2.43 dBic的测量增益，并且通过保持天线的紧凑性而无需使用复杂的过孔，可以获得优于87％的辐射效率。同样，预期的天线可提供良好的AR波束宽度，为80°（+ 40°至-40°），并且对于theta =±36°以及所有phi值（phi = 0 ⁰均具有正增益值）–360°）在5.55 GHz。此外，与传统的单极天线相比，预期的天线可提供42.85％的小型化。因此，目标天线非常适合5.80 GHz WLAN（5.725–5.875 GHz）和5.5 GHz WiMAX（5.25–5.85 GHz）应用。