This paper introduces new compact microstrip line fed dual-band printed MIMO antennas resonating at 28 GHz and 38 GHz which are appropriate for 5G mobile communications. The first design in this work is a two-element conventional rectangular microstrip patch antenna with inset feed intended for 28 GHz and 38 GHz bands. The second design is symmetric dual-band two-element MIMO slotted-rectangular patches via microstrip inset fed lines. The dual-band response is attained from inverted I-shaped slots inserted in main patches. The third design is symmetric dual-band four-element MIMO antenna with inverted I-shaped slotted rectangular patches. A slot formed DGS is inserted in the partial rectangular ground plane. The substrate size is 55 x 110 mm2, while the introduced antennas have very modest planar configurations and inhabit an insignificant area which make them fit easier within handset devices for the forthcoming 5G mobile communications. Better return losses and larger bandwidths are realized. The MIMO antennas have low mutual coupling without using any added constructions. The antenna systems offer appropriate values of directivity, gain, and radiation efficiency with anticipated reflection and correlation coefficient characteristics which are seemly for 5G mobile applications. The antenna systems are fabricated by a photolithography process that uses optic-radiation to copy the mask on a silicon slab by the aid of photoresist layers and measured using Vector Network Analyzer ZVA 67 (measures up to 67 GHz frequency) with a port impedance of 50 Ω.
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