A Dual-Band Footwear Textile Antenna for LoRa Off-Body Communication

In this paper, a dual-band footwear textile antenna is proposed for off-body network communication, which covers 433 MHz, 868 MHz and 915 MHz bands of LoRa applications. Due to the good structural flexibility of the textile material, the proposed antenna is closely conformal to the heel to accommodate the tight space at the shoes. To achieve dual-band performance, the radiation patch is slotted to generate a low frequency resonance of 433 MHz, while an additional strip is loaded perpendicularly to the feeding line to generate a high frequency resonance. The simulation results show that the bandwidths of the antenna are 51 MHz and 257 MHz in the lower and upper bands, which are enough to cover most frequency bands of LoRa communication. Besides, the measurement results illustrate the antenna has good horizontal omnidirectional radiation characteristics for off-body communication.