A Yagi–Uda Antenna With Load and Additional Reflector for Near-Field UHF RFID

Study of a Multi-Loop Travelling Wave UHF RFID Near-Field Antenna

“…As for [29], it has a very large reading area of 440 mm × 160 mm, and has used 17 dBm input power and therefore not suitable to be included and compared with the other reference antennas in Table 2 (as all reference antennas in Table 2 are using 30 dBm input power). Even though [29] was fed by a lower input power and has exhibited a maximum read range of 14 cm, while most of the tags (reading rate >95%) are successfully read at 10 mm, the full range read distance of [29] was too short or does not exist. In addition, the operation band of [29] was 880-980 MHz that cannot cover the ETSI band (865-868 MHz).…”

“…Even though [29] was fed by a lower input power and has exhibited a maximum read range of 14 cm, while most of the tags (reading rate >95%) are successfully read at 10 mm, the full range read distance of [29] was too short or does not exist. In addition, the operation band of [29] was 880-980 MHz that cannot cover the ETSI band (865-868 MHz).…”

Transmission Lines to Enhance the Reading of UHF RFID Tags on Small Metallic Objects

“…In the present case, considering that the TO are small enough not to disturb the magnetic field created by the CBCPW line, the coupling coefficient ‫ܥ‬ ே depends on the frequency of operation, the distance between the central line and the tag, the missalignement between the tags and the line Hence, according to [3] [12],the magnitude of the magnetic field normal to the surface of the tag (referred to as ȁ‫ܪ‬ ௭ ȁ ) should be greater than the threshold value ‫ܪ‬ ௧ which is about -30 dBA/m for the Dash XXS by Xeraf, a passive UHF Class 1 Gen 2 tag [13]. It is equipped with the Alien Higgs-3 chip that has a typical sensitivity, ܲ ௧ , of -17dBm.…”

“…Recently, Ultra-High Frequency (UHF) near-field RFID technology received a lot of attention due to the promising opportunities in item-level RFID applications such as sensitive products tracking, pharmaceutical, logistics, transport and medical products [2]. Moreover, near-field systems allow a considerable size reduction of tags compare to those used in far-field systems, expending the range of applications of RFID to extremely small items [3].…”

Compact dual‐wideband multi‐mode printed quasi‐Yagi antenna with dual‐driven elements

“…Yagi antennas are an appealing antennas for use in mobile devices, considering their stable gain versus frequency [1,2]. However, for operation at frequencies at the lower part of the ultra-high frequency (UHF) band, the size of a conventional Yagi antenna becomes too large for practical use [3,4]. The reason is that the driven element of a Yagi antenna is generally a half-wavelength dipole followed by directors and reflectors also with approximately quarter-wavelength separations [5].…”