A Dual-Sense Circularly Polarized Flexible Asymmetric CPW-Based Antenna

A conformable, Circularly Polarized (CP), with dual-senses of rotation, antenna is introduced. The antenna has an area of $25\ \text{mm}\times 26.5\ \text{mm}$ , where Co-Planar Waveguide (CPW) excitation technique is the means for feeding. Rogers Ultralam 3850 substrate material is used to ensure that the antenna is flexible. By designing an asymmetric CPW ground in the essence of elongating the length of one ground plane, with respect to the second one, and engraving a T-shaped slot on the left side CPW ground, Left Hand Circular Polarization (LHCP) and Right-Hand Circular Polarization (RHCP) are accomplished. The antenna resonates at 5.8 GHz of the Industrial, Scientific, and Medical (ISM)-band, with 1.75 GHz–10 dB bandwidth, realized gain of 2.4 dBic. It possesses CP features with Axial Ratio (AR) of 0.27 dB at the boresight direction, and 225 MHz worth of 3 dB-AR bandwidth. Thanks to the achieved specifications, it is a good candidate for flexible CP-related wearable applications.