Compact Ring Slot Antenna With Harmonic Suppression

摘要

Harmonic suppression antennas are widely used in the microwave power transmission and active antenna systems. In this letter, a square ring slot loaded with two side slots is constructed as the radiating element. Meanwhile, a bottom transverse slot orthogonal to the microstrip feedline is introduced as the harmonic suppression unit. In fact, the part of microstrip feedline that extends into the slot ring also has an inhibitory effect on the harmonics. In this way, a compact slot antenna with harmonic suppression is constructed. For the proposed antenna, the fundamental frequency and harmonic rejection can also be adjusted independently, so the antenna structure is easy to implement. The experimental results of the prototype antenna show that the designed antenna achieves good suppression for the second- and third-order harmonics.