A New Design of a Spiral UHF RFID Tag Dipole Antenna Mounted on Metallic Objects

This paper deals with the design of a new structure of an Ultra High Frequency (UHF) dipole antenna for RFID TAG. To design such antenna, we have to optimize such structure by taking into account the input impedance matching by reaching an input impedance of the antenna which is equal to the conjugate one of the microchips, the implementation of this type of antenna on an object with a metallic surface, influences the efficiency of these parameters. Knowing that the manufacturing cost of an antenna is one of the most important factors that must be taken into consideration during the design and realization phase. To achieve this goal, this paper deals with the design of a new and a simple Ultra High Frequency RFID tag antenna formed from a folded spiral dipole printed on a FR4 substrate having a dielectric constant
$\varepsilon \mathrm{r}=4.4$
, and loss tangent
$\tan\delta=0.02$
, the antenna structure is matched to an “ALIEN HIGGS 4” UHF microchip in strap packaging, it can be mounted on a metallic surface, and it should be noted that the structure does not include metal vias or short-circuiting stubs.