Read Range Investigation of RFID Tag on Human Chest

Abstract

Radio Frequency Identification (RFID) technology for automatic identification, tracking, and monitoring of human is in great demand by the healthcare industry. The existence of passive tag with proximity to human body in general, represents an intrinsic challenge because of the high losses of body tissues A commercial passive ultra-high frequency (UHF) RFID tag with 860 MHz-960 MHz operating frequency range is modelled to study and analyze the effect on the read range parameter by placing the RFID tag in proximity to human body model (the chest) with respect to the placement of pocket position of any shirt The body model of the chest is consisting of three layers which are skin, fat and muscle. The commercial RFID tag that has been used for this study was INLAY-9662. The measurement is done on the commercial tag prior to modelling and simulation in the CST. Furthermore, the simulation was carried on two conditions: (1) in free-space, and (2) in proximity to human body. In addition, 1 mm, 3 mm and 10 mm have been set as the gap between the modelled tag and the chest model to examine the impacted read range at different distances. The results obtained have shown some variations when the distances are varied from the human chest. The read range were achieved at 0.5 m, 1.3 m and 2.4 m for 1 mm, 3 mm and 10 mm respectively. This study has shown the capabilities of human body to reduce the efficiency of the read range whenever RFID tags are placed in proximity to human body.

Effect of Human Body to the Read Range of Wireless Communication Devices and Wearable Antenna Worn in Close Proximity

“…The finest and most ideal value in relation to Figure 2 can then be selected. At f = 920 MHz, the S11 slope is optimal and is less than -2.5 db (Salem, 2022).…”

“…The read range of the UHF-RFID tag antenna might be significantly impacted (El Bakkali et al, 2021). As a result, this study makes use of the human body's electrical characteristics, which were gathered from the datasheet and are displayed in Table 1 (Salem, 2022).…”

“…Table 2 computes the average conductivity and permittivity values for the chest region. Prior to the body model being designed in CST and shown in Figure 1, it is also shown in Table 3 (Salem, 2022).…”

“…In human body circumstances, the closer the tag is to the body, the more the read range is impacted by the characteristics of the body. It displays the read range while taking clothing and body movement into account as a spacing gap between the body and RFID tag model, and it provided various waves under the free space condition (Salem, 2022). The read range is more significantly impacted by human body characteristics when the tag is put near to the body than when it is farther away.…”

“…The slopes for both circumstances are also combined shown in Figure 4. The human body's dielectric biological matter and the object's high loss dielectric constants produce a variance in performance when an RFID tag is placed close to a human body, which reduces radiation efficiency and causes detuning of the tag (Salem, 2022).…”