In this paper, the realization of a circularly polarized multiple-input, multiple-output (MIMO) array antenna with a cosecant squared pattern, is presented. The proposed antenna structure consists of microstrip patches with rectangular slots etched from the top. The desired radiation pattern is generated using amplitude tapering obtained by modifying patch widths and slot lengths, based upon the amplitude coefficients of the Woodward-Lawson method for pattern synthesis. A MIMO arrangement with circular polarization is formed by connecting two such arrays excited by two ports. A Z -shaped slot is used to minimize the mutual coupling. Using two shorting pins, the isolation is enhanced and kept above 30 dB. This arrangement offers a small size (52 mm ×24 mm × 0.8 mm), wide bandwidth, and high gain antenna operating at 13.2 and 16.6 GHz. The antenna operates in a wide bandwidth, from 12.6 GHz to 14.25 GHz, and from 16 to 17.61 GHz, with admirable directional characteristics. The achieved gain is 16.9 dB and 16.6 dB with a cosecant pattern and low side lobe level. The analysis of the, VSWR, gain, axial ratio, group delay, efficiency, and MIMO performance metrics are also investigated, both in simulation and in experiment.