[11] “Polarization-Reconfigurable and Frequency-Tunable Dipole Antenna Using Active AMC Structures,” IEEE Access, vol. 7, pp. 77792-77803, 2019.

作者: Dongxu Chen, Wanchen Yang, Wenquan Che*, Quan Xue, Lizheng Gu

摘要：A polarization-reconfigurable and frequency-tunable mechanism based on an active artificial magnetic conductor (AMC) structure is proposed. The active AMC unit cell consists of a four-corner-cut inner patch and four triangles loaded with four varactors, and it can realize polarization-reconfigurable and frequency-tunable reflection characteristics by adjusting the capacitance of the varactors.By employing it as a ground plane of a pair of linearly-polarized dipole antennas,a multi-functional antenna can be well designed with polarization reconfigurability and frequency-tuning capability.By controlling the DC bias of the varactors accordingly,the three polarization states of right-/left-handed circular polarization(R/LHCP) and linear polarization (LP) can be switched, respectively, while the operating frequency of each polarization can be flexibly tuned.The measured tuning frequency ratio for the LP state(|S11| < −10dB)can reach 1.56:1,while the ratio for either the LHCP or RHCP state (axialratio< 3dB)is about1.28:1.Moreover,a large bandwidth for each polarization state can be obtained,where the bandwidths are up to17.1% and 8.7%,respectively,for the LP and CP states. Besides, it is more flexible for the CP states since the bandwidth can be adjusted. For a demonstration,one prototype of the proposed antenna is fabricated and measured.The agreement between the theoretical and measured results indicates good performances of the proposed antenna.