Miniaturized wideband dual linearly and circularly polarized printed square slot antenna for multiradio wireless systems

A dual symmetrical coplanar waveguide (CPW)-fed small size wideband printed square slot antenna (SSA) with dual linearly and circularly polarized radiation capability is presented. The antenna is composed using a square slot, two symmetrical orthogonal CPW feed lines connected to horizontal and vertical arm of L-shaped radiator, an embedded parasitic inverted-L strip at the lower left corner of the square ground slot and engraving slots in the ground plane. Circular polarization (CP) is achieved due to two orthogonal CPW feed lines and a common L-shaped radiator. Isolation between ports is improved by engraving slots at the lower left corner of ground plane and embedded parasitic inverted-L strip. The sense of dual-polarization can be changed in pass-band by changing the port excitation. Measured antenna reveals that an 84.4% (4.6 GHz, 3.15-7.75 GHz) −10 dB impedance bandwidth (IBW) and about 33% (2.03 GHz, 5.12-7.15 GHz) 3-dB axial ratio bandwidth (ARBW). Isolation between ports <−16 dB is achieved over usable CP band.