In Fig. 2a a possible modular configuration is shown as well as preliminary results in terms of S-parameters in the FCC
UHF RFID operating band (902-928 MHz). In this example, a microstrip spiral-shaped transmission line antenna is
placed in the central area, and a 2x1 inverted-F meandered dipoles [7] array is realized in the lateral zone near the
edges. While the transmission line is responsible for the EM field generated just above the antenna surface (near-field
reactive region), the 2x1 array can be properly fed in order to maximize the EM field in the near-field reactive region.
The two radiating elements can be series-fed or, alternatively, connected to a switch and sequentially fed by using a
proper power control algorithm in order to meet the NF-UHF RFID desktop reader requirements