Planar slot antenna with circular and vertical polarization diversity

This article proposes an easily manufacturable multifunction two-port planar slot antenna, radiating omnidirectional linearly polarized and broadside circularly polarized radia- tion patterns through a common slot in an overlappin g fre quency bandwidth at 5.9 GHz of 2.56%, with inter-port coupling below 245 dB.Nicholas P. Lawrence, Christophe Fumeaux, Derek Abbot