A Novel Ultrawideband Exponentially Tapered Slot Antenna of Combined Electric-Magnetic Type

A novel exponentially tapered slot antenna with ultrawide bandwidth and small late-time ring is presented. A microstrip-to-coplanar-stripline (CPS) transition of Chebyshev multisection type is used as feeding transmission. The exponentially tapered slot, which is considered as electric-type radiator (ER), is combined with a magnetic-type radiator (MR) to achieve ultrawideband performance and small size. The MR is completed by a lumped resistor bridged between the loop arm and the transmission ground. The measured impedance bandwidth (VSWR <; 2) of optimized antenna is 0.65 ~ 5.9 GHz, which agrees well with the simulated results. The measured gain is almost 3 dBi in the whole band, and the front-to-back ratio is about 15 dB.