DESIGN OF A COMPACT CPW-FEED ASYMMETRIC ELLIPTICAL SLOT ULTRAWIDEBAND ANTENNA FOR HIGH GAIN

摘要

A compact, CPW-feed slot antenna for ultrawideband applications is proposed. The antenna uses an elliptical patch as radiating element and an asymmetric slotted ground plane to provide a measured usable bandwidth of 120% (2.81-11.2 GHz). The asymmetric slot in the ground plane creates an extra inductive reactance which neutralizes the capacitive effect of the open ended elliptical patch and results into wider impedance matching. To improve the gain of the proposed antenna, a three metallic layer frequency selective surfaces (FSSs) of overall thickness 3.5 mm and with a stop band (transmission<-20 dB) of 8.3 GHz (2.6-10.9 GHz) is proposed. With the FSS, there is a 4-5 dBi improvement in the antenna peak gain and the back lobes are reduced by around 10 dBi. The measured and simulated results are in good agreement. (c) 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:314-319, 2015