Research On Pattern Reconigurable Microstrip Diole Antenna

With the development of radio communication, antenna as a key technique became more and more important. The novel pattern reconfigurable antenna appeared in recent years. By better directing signals toward intended users according to the environments, the pattern reconfigurable antenna can enable the system to avoid interference, improve security and save energy.This paper introduces the novel method to design the pattern reconfigurable antenna based on the theory of phased antenna array. The switches embedded in the antenna, together with the deformation structures of power divider and hybrid ring, are used to control the current phase of different radiation elements. The radiation elements and the control elements are integrated on the same substrate. This structure can avoid using the extra control circuits of the phased antenna array. So the antenna structure is simple and easy to be integrated into equipments.In this paper, three pattern reconfigurable microstrip dipole antennas are designed. The patterns of these antennas can be shifted more than±100°. The design theory of the first antenna is derived from an example of two-element array pattern multiplication theorem. The measured results of the first antenna verify the feasibility of the introduced design method. In the following designs, the number of the radiation elements is increased, so the pattern can not only point to more directions but also cover a wider space. By changing the structure of the radiation elements, the more diversity of pattern can be obtained too.