A tunable stepped-impedance resonator using liquid crystal is demonstrated. Two resonant frequencies at 3.367 and 7.198 GHz are realized and can be continuously tuned by external applied voltages. Continuous tunable ranges of 52 and 210 MHz have been achieved at a particularly low driving voltage of 14 V, which shows good agreement with the simulation results. The voltage-induced hysteresis phenomenon is also investigated. This device also has a low insertion loss of −2.9 and −4 dB for the two resonant frequencies and the return losses are less than −21.5 dB. This work provides a new protocol to realize a tunable frequency for communication systems.

演示了使用液晶的可调阶梯阻抗谐振器。实现了 3.367 和 7.198 GHz 的两个谐振频率，并且可以通过外部施加的电压连续调谐。在 14 V 的特别低驱动电压下实现了 52 和 210 MHz 的连续可调范围，这与仿真结果非常吻合。还研究了电压引起的滞后现象。对于两个谐振频率，该器件还具有 -2.9 和 -4 dB 的低插入损耗，并且回波损耗小于 -21.5 dB。这项工作提供了一种新的协议来实现通信系统的可调频率。