A compact dual-band dual-polarized patch antenna for 900/1800-MHz cellular systems

A novel compact design for achieving dual-band dual-polarized radiation suitable for applications in the 900/1800-MHz cellular systems is presented. The proposed antenna consists of a rectangular ring patch (for the 900-MHz operation) and a notched rectangular patch (for the 1800-MHz operation), which are printed on the same layer, and each patch is aperture-coupled by two H-shaped coupling slots to generate two orthogonal linearly polarized waves. By further incorporating a properly designed feed network, the proposed antenna shows good port decoupling of less than -39 dB and -34 dB for dual linear polarizations in the 900- and 1800-MHz bands, respectively. Details of the antenna design and experimental results are presented.