DUAL BAND CIRCULAR POLARIZED PRINTED DIPOLE ANTENNA FOR S AND C BAND WIRELESS APPLICATIONS

In this article, a modified circular shape printed dipole structure is studied to achieve wide bandwidth and dual-band circular polarization (CP) behavior along with dual polarizations. The idea behind this structure is that asymmetric geometry can give rise to circular polarization with an optimized position of coaxial probe feed. The circular patches on both sides of the substrate are altered with elliptical slots at an optimized location in association with opening slots. With these alterations the impedance bandwidth for S11 < −10 dB is ranging from 2.36–7.34 GHz (4.98 GHz) which is nearly 102.5% about mid-point frequency 4.85 GHz. The antenna resonates at a lower band (1.55 GHz) and shows linear polarization (LP) operation at that band whereas dual CP bands with dual senses are obtained at higher frequency ranges 4.00–4.60 GHz and 6.07–7.13 GHz respectively with 3-dB axial ratio bandwidth of 13.7% and 16.6%. The simulated and measured experimental results are in close agreement. This antenna is suitable to be used for navigation purposes, radar communication, and wireless communication (especially wireless avionics intra communications) in S and C bands, respectively.