The design of an aperture-coupled microstrip antenna with switchable polarization is presented. The antenna is excited by a series microstrip-line-feed configuration through the coupling of a ring slot in the ground plane. For the ring-slot-coupled microstrip antenna, it is found that the minimum axial ratio in the 10 dB-input-impedance bandwidth can be varied between 0.4 and 23 dB when the length of the series stub is changed. Therefore, the antenna can radiate linear or circular polarization with good performances by selecting a proper length of the stub. To realize the voltage-controlled polarization switching, one PIN diode is integrated into the ring-slot-coupled microstrip antenna. Two typical layouts are indicated and their antenna prototypes are implemented. Details of the measured and simulated results are also presented.
All Science Journal Classification (ASJC) codes
- Electrical and Electronic Engineering