In this paper, design of a reflective surface -based circularly polarized ( CP) antenna for providing omni coverage in the communication application is discussed. The antenna consists of two reflective surfaces and a waveguide polarizer. The antenna designed in this paper has omni coverage in the azimuthal plane and? 10°to+40°coverage in the elevation plane. The antenna has been simulated by the high -frequency structure simulator ( HFSS ) software using proper boundary conditions. The simulated results and measured results are presented. The proposed antenna has the advantages of simple structure, small volume, wide coverage and easy to fabricate.