An Antenna with Quasi-Isotropic Radiation Pattern Designed with Bent Dipoles

Internet of Things (IoT) devices, typically, need electrically small antennas that can maintain orientation insensitive communication. This is feasible with quasi-isotropic radiation patterns. This paper presents a theoretical model, based on annular currents, for the design of antennas with quasi isotropic radiation patterns. The theoretical model is then used to design an antenna that comprises two orthogonal bent dipoles. The effect of the bending radius on the radiation isotropy performance has been studied. The theoretical results obtained using the annular current model have been verified by simulations and a fabricated antenna prototype. Measured results are in decent agreement with the simulated results and a quasi-isotropic radiation pattern of the antenna with a gain variation of 5.7 dB has been achieved.