Experimental Evaluation of Sub-6 GHz On/Off-Body LoS and NLoS Links based on Textile Single-Wire Transmission (SWTLs)

Single-wire transmission lines (SWTLs) were recently proposed as an enabler of low-loss conformable on-body links, and demonstrated up to mmWave bands. However, as structures with high spurious radiation, they show potential for dual-mode on/off-body operation, but have not been explored for this purpose. Herein, the off-body transmission parameters of wearable textile-based SWTLs are presented for the first time, demonstrating their ability to simultaneously operation in on/off-body links. Across all tested on-body links, line-of-sight (LOS) and non-line-of-sight (NLOS), the SWTL presents a 10 to 40 dB channel gain enhancement compared to on-body dipoles up to 4 GHz, while retaining its broadband off-body radiation. The results further highlight the benefits of realising quasi-wireless networks based on broadband SWTLs.