UHF pure near‐field RFID reader antenna based on CSRR

Abstract

An ultra‐high frequency (UHF) travelling wave antenna based on complementary split ring resonator (CSRR) element is investigated in this study for pure near‐field radio frequency identification (RFID) system. The proposed antenna consists of a T‐type power divider, 180° phase shifter, two microstrip transmission lines ended with two 50thinmathspacenormalΩ resistors and the metal ground loaded CSRR elements. The CSRR elements are loaded on the metal floor corresponding to the minimum current points and middle of the two transmission lines. The CSRR elements resonate at the centre frequency and introduce coupling to enhance the magnetic field. The measured −10 dB impedance bandwidth of the proposed antenna is 46 MHz (889–935 MHz), which covers the standards of Chinese and American bands. The reading regions for near‐field tag, far‐field tag and anti‐metal tag are 400×200×10thinmathspacenormalmm3, 400×200×70thinmathspacenormalmm3 and 400×200×60thinmathspacenormalmm3, respectively. The far‐field gain is less than −22 dBi, which makes the antenna suitable for the pure near‐field application.

A universal UHF near‐field RFID reader antenna with wide bandwidth and adjustable reading area

“…Subsequently, the TW structure is adopted to increase the bandwidth, and the magnetic field uniformity and strength are improved by deploying the complementary open resonant ring (CSRR). Whereas, the impedance bandwidth cannot cover the universal ultrahigh‐frequency (UHF) RFID frequency band of 840–960 MHz 13,14 . It reveals that the difficulty of near‐field reader antenna design is to obtain a wide band covering the universal UHF RFID frequency band, adjustable reading area with strong and uniform magnetic field distribution, simultaneously.…”

“…There are mainly four methods for realizing magnetic coupling near-field reader antenna, namely, zero-phase shift line loop, [6][7][8] meander line, 9,10 oppositely directed current (ODC), 11,12 and traveling-wave (TW) structure. 13,14 Zero-phase shift line loop antenna generates a uniform magnetic field distribution in the reading area. But a high far-field gain is suffered.…”

“…Whereas, the impedance bandwidth cannot cover the universal ultrahigh-frequency (UHF) RFID frequency band of 840-960 MHz. 13,14 It reveals that the difficulty of near-field reader antenna design is to obtain a wide band covering the universal UHF RFID frequency band, adjustable reading area with strong and uniform magnetic field distribution, simultaneously.…”

Efficiency Analysis of Sports Equipment Batch Management Based on Antimetal RFID Tag

“…In the vigorous development stage of college sports, more teaching projects must be completed with the help of sports equipment. In physical education, colleges should not only provide sports equipment but also manage sports equipment, so as to provide better serve physical education [1,2].…”