TABLE III.
Representatives of Antennas for RFID Applications
| Ref. | Antenna Configuration | Size (L×W×H) (mm3) | Frequency (GHz) | Maximum Realized Gain (dBi) | Bandwidth (MHz) | Fractional Bandwidth (%) | Radiation Efficiency (%) | Characteristics |
|---|---|---|---|---|---|---|---|---|
| [84] | Dual-layer, two patches fed via a PIFA array | 26×14×2.4 | 0.923 | −1.4 | 16* | 1.7* | 23 | Electrically small, metal-mountable |
| [85] | A meandered patch fed by a coupled microstrip line | 100×50×0.8 | 0.915 | −3.8§ | 43 | 4.7 | N.A. | Broadband, metal-mountable |
| [86] | Slotted, magnetic dipole-based antenna | 180×60×20† | 0.92 | 5.3 | 62 | 6.7 | N.A. | Low-profile, vertical polarized |
| [87] | A single longer dipole and a pair of shorter dipoles | 43×26×0.5† | 2.4 5 |
7.5 9.5 |
120 2100 |
5 42 |
>95 | Dual-band, single-substrate |
| [88] | SIR coupled dipole antenna | 25×9×1.6 | 2.4 5–6 |
2.6 3.6 |
95 1380 |
4.0 26.5 |
88.6 96.87 |
Dual-band, broadband, electrically small |
| [89] | Hybrid-fed microstrip antenna | ~35×35×1.5† | 3 6 |
1.17 3.33 |
50 240 |
1.7 4.0 |
40–70 | Dual-fed, low-profile |
| [90] | Diamond-shaped patch antenna | 150×150×1.66† | 0.915 2.45 |
7.8 9.4 |
18 80 |
2.0 3.3 |
87 94 |
Dual-band, single-substrate |
| [91] | Rectangular slot antenna | 2.5×2.5×2.5† | 24 40 |
−1 0 | ~5000 ~8000 |
19 20 |
41 31 |
On chip, dual-band, millimeter-wave |
*
represents −3 dB (half-power) bandwidth/fractional bandwidth, while others represent −10 dB bandwidth/fractional bandwidth.
§
represents that the results are obtained from simulations, while others are obtained from measurements.
†
refers solely to the dimensions of the resonator or radiator and does not encompass the overall dimensions of the antenna.