This paper presents a compact slotted MIMO cube antenna operating at 5.8 GHz, consisting of three orthogonal slots, each with a distinct main direction of radiation. Each slot produces linear polarization enabling the structure to radiate three orthogonal polarizations. This provides spatial diversity which helps mitigating the effects of multipath propagation and enhances the diversity gain. The cube is filled with a dielectric with a relative permittivity, εr thus reducing the minimum dimension of the cube by a factor of 1/√εr . The antenna has a return loss of 20 dB and a coupling of less than -26 dB between the ports. This paper describes the principle operation as well as the design and manufacturing process of the proposed antenna.
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