A Tunable Dipole Antenna Controlled by Motor

In this paper, a new structure of tunable dipole antenna that controlled by motor is proposed. Based on half-wave dipole antenna, this antenna adds a motor-controlled rotating structure in the middle of the dipole. By changing the length of the loop arm connected to the dipole arm, the continuous adjustment of the working frequency is realized. The structure can work effectively in various frequency bands, and shows different tunable ranges according to different sizes and ratios. In a specific implementation, simulation results show that the antenna has a tunable range of 847MHz to 930MHz and a minimum -10 dB bandwidth of 108 MHz. The radiation pattern of the antenna has a directivity from 2.27 dBi to 2.18 dBi and a 3 dB beamwidth from 77.5° to 79.0°. All point to the good application potential of this design in wireless communication fields such as RFID readers.