A Dual-Band Quad-Element MIMO Antenna Covering Wide Bandwidth in 5G New Radio and mm-Wave Bands with Equivalent Circuit Analysis

A compact quad-element multiple-input multiple-output (MIMO) antenna design for dual-band operation (38.07 and 42.87 GHz) has been proposed for fifth-generation new radio and mm-wave bands. The overall dimension of the proposed design is 1.90 lambda(0 )x 2.53 lambda(0 )x 0.06 lambda(0) (or 15 mm x 20 mm x 0.508 mm), where lambda(0) represents the wavelength corresponding to 38.07 GHz. The proposed antenna consists of slotted and truncated rectangular patch with H-shaped arms and partial ground structure. Parametric analysis with respect to ground width (W-g) for reflection coefficient and antenna gain has been performed to find the optimum values of W-g which satisfies the required bandwidth and bands of operation (n259 and n260). The bandwidth achieved by the proposed quad-element MIMO antenna is 12.25 GHz (31.85-44.37 GHz). The isolation achieved by this antenna for the entire band of operation is < -20 dB. Moreover, the proposed design results stable radiation patterns along with high gain of 5.33 dBi and radiation efficiency of > 97%. The different MIMO diversity parameters achieved by the quad-element antenna are < 0.025 for envelope correlation coefficient, 9.99 dB for diversity gain, and < 0.4 bits/s/Hz for channel capacity loss in the entire operating band. The achieved channel capacity has also been analyzed for this design which resulted to approximate to 18.5 bits/s/Hz. Furthermore, the equivalent circuit for the proposed MIMO antenna has also been presented and validated.