A Pattern Reconfigurable Antenna Applied for Automobile 5G Communication

A pattern reconfigurable antenna is proposed to achieve four different radiation patterns by controlling the switching state of the PIN diodes. The structure is achieved by uniting a center-fed microstrip shorted patch and four parasitical monopoles, and eight PIN diodes are introduced to control monopoles. The monopole which is vertical to the substrate is working as an electric current source. The loaded monopoles break the symmetry of the center-fed microstrip antenna, then original patch antenna can work as in-phase equivalent magnetic current sources. Then complementary sources are generated by orthogonal magnetic current source and electric current source, which can ensure that the antenna has good unidirectional radiation characteristics in one state. By switching the ON/OFF states of the PIN diodes, four different modes with endfire radiation patterns can be obtained and then this antenna can be used to obtain equivalent omnidirectional coverage. The antenna works in the 5G frequency band, and the complete microstrip floor characteristics make it suitable for automobile 5G communication applications.