8x8 Near-Field Focused Circularly Polarized Cylindrical DRA Array for RFID Applications

The design of an 8x8 near-field focused circularly polarized dielectric resonator antenna (DRA) array for fixed RFID reader applications at 5.8 GHz is presented. The proposed antenna array consists of 64-element of cylindrical dielectric resonator antennas (CDRA) with two orthogonal feeding probes located inside the CDRA element. A single element CDRA with supporting arms is used as a building block of the array provided good impedance matching and circular polarization at 5.8 GHz. The perforation technique is used for the supporting arms to reduce the manufacturing complexities in the CDRA mounting over the ground plane. The sequential feeding technique is applied to improve the gain and circular polarization bandwidth of the single element and the array. The characteristics of the near-field focused array are introduced compared to that of the uniformly phased array. The finite integral technique and the finite element method are used to compute the array performance.