MULTI FREQUENCY SUPER FORMULA BASED CIRCULARLY POLARIZED PATCH ANTENNA WITH CPW FEED

Abstract

A multi frequency broadband circularly polarized patch antenna based on Gelies’s super-formula is presented in this paper. The multiband characteristics of the antenna are achieved by its sunflower inspired multi ringed patch antenna shape. The antenna is designed using a 59.691mm × 60.41 mm   Rogers RO4003 substrate and the structure is fed using a CPW feed. The use of CPW feed has increased the bandwidth of the antenna from 0.88 GHz -1.61GHz in L band, 2.46 GHz -2.60 GHz in S band and 4.87 GHz -6.49 GHz in C band.  By introducing slots in the ground plane circular polarization is achieved in the C band. Application of the proposed multi frequency broadband circularly polarized patch antenna structure with 1.06 GHz., 2.56 GHz. and 5.8 GHz central frequencies are demonstrated experimentally. Measured and simulated results of the magnitude of S11, radiation patterns and realized gains show good agreement.