In this paper, a novel compact single element G-shaped Asymmetric Coplanar Strip (ACS) fed antenna and its four-element printed multiple-input multiple-output (MIMO) antenna have been presented with multi-band frequency characteristics. The proposed MIMO antenna has been fabricated on an FR-4 substrate (46 × 46 × 1.6) mm3 with dielectric constant εr = 4.4. The desired isolation between the elements (-18 dB) is achieved by placing the antenna elements orthogonal to each other. Simulated and measured results show that return loss (S11) for the proposed MIMO antenna is less than -10 dB in the operating bands, with frequency ranging 2.30-2.45 GHz, 3.36-3.65 GHz, and 4.53-5.88 GHz, respectively, which ensures its operation in multiple frequency bands. Moreover, these bands are obtained for 2.3 GHz WiBro, LTE and 5G NR to cover B40/B42/N30/N40/N97 together with 3.5 GHz/5 GHz WiMAX/WLAN band applications. Meanwhile, the diversity performance characteristics like ECC (Envelope Correlation Coefficient), MEG (Mean Effective Gain), DG (Diversity Gain), Total Active Reflection Coefficient (TARC), and Channel Capacity Loss (CCL) have been calculated and are presented in this paper. The correlation coefficient is found to be less than 0.001 with a diversity gain greater than 9.95, and an acceptable channel capacity loss is less than 0.4 bits/s/Hz.