A Compact Planar Quasi Yagi Antenna With Bandpass Filtering Response
A planar quasi Yagi antenna with bandpass filtering response is presented. The quasi Yagi antenna consists of a double sided printed driven dipole, an offset double sided parallel strip line (DSPSL) director, a DSPSL reflector, and an offset DSPSL parasitic element. Both the reflector and the parasitic element can produce an extra radiation null at the band edges of the passband, and the parasitic element can also generate an additional resonance within the passband. As a result, a compact wideband quasi Yagi antenna with quasi elliptic bandpass filtering response is obtained, without requiring any extra filtering circuit. In addition, the antenna is fed by a balanced DSPSL, and therefore, no balun is needed, leading to a very simple feeding structure. For demonstration, a prototype operating at 2.4 GHz was designed and measured. The prototype has a low profile of $0.006\lambda _{0} a 10 dB impedance bandwidth of 30.4% an average gain of 5.7 dBi over the passband, and an out of band suppression level of about 20 dB in the near stopbands.
IEEE Access