In this paper, we propose a novel miniaturized, flexible wearable rectangular patch antenna with Defected Ground Structure (DGS) for wireless body area network application. The resonance frequency and bandwidth of this antenna, which operates in the ISM (Industrial, Scientific, and Medical) frequency band, are 2.45 GHz and 0.379 GHz, respectively. One of the most commonly utilized fabrics for wearable antenna, denim jeans is used as the substrate whereas copper tape is used for fabricating the patch, feed and ground for the designed antenna. The patch antenna has rectangular and circular slots and a deflected ground structure (DGS) featuring a split ring resonator. The antenna is feed via a 50 Ω microstrip line. The antenna measures 31 × 42 × 0.6 mm3 (0.25λo mm × 0.34λo mm × 0.005λo mm) in total. The designed antenna operates at the required frequency while maintaining high levels of directivity, gain, and Reflection Coefficient (S11), with values of 2.93 dBi, 2.627 dBi, and − 41.723 dB, respectively. The antenna has a radiation efficiency of 90.86%. To determine if the antenna was suitable for wearable use, its performance was examined under various bending conditions for varied radii of curvature. The Specific Absorption Rate (SAR) of the final antenna was tested and found to be 0.0548 w/kg for 1 g of tissue, which is well acceptable according to IEEE and FCC regulations. The antenna was designed and simulated using Computer Simulation Technology software and tested using a vector network analyzer. This paper contains the experimental results from the antenna prototype as well as a detailed description of the proposed antenna design. Its small size, return loss, gain, and SAR values indicate that the designed antenna is ideal for body-worn applications. The field of smart wearable textiles antenna may be able to use the suggested antenna in practical ways.
