Impact of Body Proximity on Body Worn Textile Antenna Performance

This study evaluates the performance of a textile antenna close to a human body phantom developed for on-body wireless communication applications. A rectangular textile antenna (RTA) with fabric (wash cotton, polycot, and polyester) substrate has been designed in 2.45 GHz WLAN band. The antennas are also analyzed in close proximity (2 mm away) to a three-layered (skin, fat, and muscle) flat human body tissue model (HBTM). A frequency detuning and reduction in antenna performance are noticed after applying flat HBTM. The curtain cotton made RMPA shows better return loss (−54.5843 dB and −49.7967 dB), peak directivity (9.220 dBi and 9.106 dBi), gain (7.965 dBi and 7.732 dBi), and efficiency (76.12% and 74.25%) for both off body and on body by maintaining a bandwidth of 100.3 MHz and 99.8 MHz. The Specific Absorption Rate (SAR) recorded for RMPA (curtain cotton) is 0.0277 W/kg< 2 W/kg averaged over 10g tissue.