A 3-D Pattern-Reconfigurable Antenna Array With Multipolarization

In this letter, a 3-D pattern-reconfigurable antenna array with multipolarization is presented. It comprises four vertically placed reconfigurable endfire dipole-pair elements and a compact four-path switchable feed network. By utilizing switchable operating dipoles of each element and appropriate pathways on the feed network, the antenna can achieve adaptive control of broadside patterns and backfire patterns with independent left-handed/right-handed circular polarization and +/- 45 degrees linear polarization in the elevation plane. Moreover, four endfire patterns with vertical polarization can be adaptively controlled in the azimuth plane. The proposed antenna is fabricated and measured. With a compact 3-D structure of 0.49 lambda(0) x 0.49 lambda(0) x 0.39 lambda(0), the measured -10 dB overlapped impedance band for the 12 operating states is 2.3-2.75 GHz (17.8%). Besides, the corresponding cross-polarization discrimination is more than 17.4 dB.