Overview of two ultra compact antennas using original materials with pattern diversity

Two designs of compact antennas dedicated to different wireless applications are presented in this paper. For both, to improve the quality of the wireless link, two radiating elements have been orthogonally integrated to apply diversity techniques. These diversity performances will be underscored by the presentation of the effective diversity gain, measured in a reverberation chamber. The first design is using a high permittivity material and combining Dielectric Resonator Antenna (DRA) resonances with a quarter-wavelength resonance of a monopole judiciously optimized to feed and set dielectric resonator modes. Finally it covers nine channels of the DVB-H band going from 790 MHz to 862 MHz, the WiFi band at 2.4 GHz and the WiMax band at 3.5 GHz and the dimensions of each radiating element are very small (λ0/15 × λ0/38 × λ0/94 at 800 MHz). The second design uses a magneto-dielectric material, it focuses on the nine channels of the DVB-H band covered by the first design. The dimensions of each radiating element are lower than the first one since the dimensions are λ0/25 × λ0/38 × λ0/95 at 800 MHz. Good performances and very good agreement between measurements and simulations have been obtained since return losses, efficiencies and realized gains are suitable and meet all applications requirements for both designs. Moreover, the operation bands are independent from the ground plane dimensions, that's why these structure are good candidates for all mobile handheld devices.