Open-ended rampart slot array antenna fed by a CPW

An open-ended rampart slot array antenna fed by a coplanar waveguide is designed and compared to the short-ended one. Experimental results show that a lower operating frequency band and better radiation characteristics of the antenna, such as higher in-band peak gains and lower H-plane sidelobe and cross-polarization levels, can be achieved by opening the rampart slotline terminations instead of shorting them.