Novel Pattern Reconfigurable Epsilon-Near-Zero (ENZ) Antenna for Intelligent IoT Communication Applications

In this paper, a novel mixed-mode-based pattern reconfigurable epsilon-near-zero (ENZ) antenna for intelligent IoT applications is presented. To flexibly manipulate the radiated wave, a new even-odd mode radiation control method is explored. Then, an aperture-shared reconfigurable metamaterial radiator is integrated by using a switchable waveguide-like ENZ resonator and a patch structure. These designs can be used to realize size reduction and beam steering. The ENZ resonator excites an even mode field distribution and radiates an omnidirectional beam. On the contrary, the patch structure excites a broadside pattern with an odd mode distribution. By mixing the even/odd modes, the field distribution of the metamaterial radiator is controlled. Thus, its radiation pattern is reconfigured. More importantly, this metamaterial radiator can adaptively switch the radiation beam in the vertical plane by creatively introducing the reconfigurable fixed-frequency ENZ resonator. Therefore, it is fully different from the conventional Yagi-type or Huygens-form reconfigurable antennas. To verify the proposed concept, a 1-D prototype is implemented. This design can achieve seven-beam switching in the vertical plane (broadside, omni., and tilted beams) by controlling the 1-bit phase / 1-bit amplitude / 1-bit aperture switching states, making it a promising candidate for intelligent IoT applications, such as smart home, digital factory, and intelligent vehicle. This work offers a new method for low-cost pattern reconfigurable adaptive antenna designs.