A New Design of K/Ka Dual-Band Aperture Coupled Antenna

A new type aperture coupled microstrip antenna is designed in this paper. It drills a circular hole in the middle of gap and works in K/Ka dual-band by changing the size of circular hole. Then a $1 \times 4$ array antenna is constituted to work at K and Ka two frequency band. This design shows that the reflection coefficient S11 less than –10 dB range from 17.5 to 20.9GHz, the impedance bandwidth of about 16.98% in K band. And S11 range from 37.3 to 38.7GHz, the impedance bandwidth of about 3.19% in Ka band. Obviously, it achieves the broadband and dual-band characteristics. And the antenna can also provide an example for design in K/Ka dual-band.