Wideband unidirectional circularly polarised slot array with integrated feeding network

A wideband planar unidirectional circularly polarised slot array is proposed. The slot array has a truly planar structure where the feeding network is integrated with the radiating elements on the same substrate, which makes it low cost and easy to fabricate. The measured result shows that the proposed array obtains an impedance bandwidth of 33.8% and an axial ratio bandwidth of 24.5%. The proposed array has a good unidirectional pattern and can be used in base station applications.