A miniaturized circularly polarized coaxial fed superstrate slot antenna for L-band application

A miniaturized circularly polarized superstrate antenna is presented in this letter. The antenna consists of a corner cut square radiating patch in which 4 arrow type slots are etched out, a superstrate placed exactly above the radiating patch and a coaxial feed. Circular polarization in the design is accomplished by the corner cuts in the radiating patch and placing the feed point below origin (0, 0, 0) along x-axis. The slot miniaturization technique results in about 73.7% and 79.8% reduction in volume and active patch area of the designed antenna. The antenna has a compact dimension of about 0.11(lambda 0)x0.11(lambda 0)x0.02(lambda 0) at a frequency of 1.21 GHz with S-11 < -10 dB bandwidth of about 3.03% (1.30-1.34 GHz). Axial ratio <3, good impedance matching, acceptable gain, radiation efficiency greater than 90%, and stable radiation characteristics are observed across the operational bandwidth of the designed antenna.