Design and Analysis of Conformal Antenna for Wearable Devices

This paper presents the design, modeling, and bending analysis of a conformal antenna operating at 2.4 GHz for wearable devices. The antenna's performance was evaluated using HFSS, focusing on return loss, geometry optimization, and bending effects. The optimal resonant frequency of 2.4 GHz was achieved for a patch length (Lp) of 41.78 mm and a width (Wp) of 50.20 mm, achieving a return loss of -34.94 dB and an impedance of 53.5 ohms. The antenna's width had minimal impact on the resonant frequency. When optimized on a Teflon substrate without bending, the antenna demonstrated excellent resonance and impedance matching, with a Voltage Standing Wave Ratio (VSWR) of 1.63 at 2.4 GHz, indicating minimal reflection. The E-plane and H-plane radiation patterns were analyzed at 2.4 GHz, showing a peak gain of 7.38 dB at a theta angle of 0 degrees. Bending analysis revealed that increased bending causes a negative shift in the resonance frequency and affects impedance matching. The proposed antenna is flexible, low-cost, and suitable for wearable medical devices and other applications in the 2.4 GHz frequency band, with return loss, VSWR, radiation pattern, and impedance results all within acceptable ranges.