  A single layer broadband millimetre wave (mm-wave) array with circular
polarisation is proposed for the fifth generation (5G) mm-wave communication
applications. The antenna element is designed to integrate the matching circuit
into a single layer. Hence no additional matching and feeding networks are
required which makes the antenna element very easy to synthesise a massive
array. The array has a 10 dB return loss bandwidth between 26 GHz and 32 GHz.
The polar angle axial ratio is less than 3 within the beamwidth of -60 degree
to 60 degree. The proposed antenna structure is simple, low cost and robust,
which we envisage suitable for the massive multiple-input and multiple-output
(MIMO) applications.
