A novel design of a 4×4 miniaturized UWB-MIMO (multiple-input, multiple-output) antenna with isolation improvement is proposed in this paper. The designing procedure of a flower-shaped MIMO antenna is done using characteristic mode analysis (CMA). The flower shaped UWB-MIMO antenna is made up of four symmetrical flower-shaped radiating elements that are isolated using an orthogonal method. The flower antenna's dimensions are 40x40x1.6 mm3 (0.44λ0x0.44λ0x0.017λ0). A flower-shaped radiator is used to get good the isolation in MIMO elements. Further isolation is enhanced by inserting a swastik-shaped stub on the ground to get return losses of S11<-10 and isolation of S12<-18 dB. The designed antenna covers the entire UWB (3.1-14 GHz) spectrum for impedance matching, including (10.7 to 11.7 GHz), 11 GHz (10.7 to 11.7 GHz), and 13 GHz (10.7 to 11.7 GHz) (12.75 to 13.25 GHz). Good diversity performance is achieved in the UWB and ITU range. The designed antenna has a gain of 5.5 dB, an efficiency of 89%, an impedance bandwidth of 123.61%, an envelope correlation coefficient of 0.0012, a diversity gain of nearer to 10 dB, a capacity channel loss of 0.29 bps/Hz, and a mean effective gain of less than -3.1 dB. The designed antenna is fabricated and tested. These simulated results are validated in state-of-the-art laboratories. According to the simulation and measurement results, this antenna is well suited for reliable wireless communication systems. The potentiality of the designed antenna is high, and the antenna is compact and portable.
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