Trapezoidal Shape Microstrip Patch Antenna Roger substrate with Complementary Split Square Resonator Enhanced by Nd:YAG Laser Processing at S-band for MIMO Wireless Communication applications

Abstract

In this paper, a trapezoidal radiating element based 4-port MIMO antenna system integrated with Complementary Split Square Resonator (CSSR) for sub-6 GHz 5G applications is presented. The antenna is constructed on a Rogers RO4350B substrate with a desired frequency of 3.545 GHz. It is found that this novel process can dramatically decrease the copper roughness from 385 nm Ra to 78 nm Ra, ~80% of reduction. This enhanced surface morphology leads to better RF properties. As indicated in the post-treatment measurements shown, excellent impedance matching is observed on each of the four ports with reflection coefficients (Sii) improved to well over -27 dB at resonance frequency, VSWR = 1.1:1: suggesting near-perfect matching and an input impedance error under the approximate 50 Ω design target. The simulated predictions are also verified to be closely matched with experimental measurements in post-laser processing of the a-Ga₂O₃, where both ECC and DG were excellent at recovering MIMO diversity performance. The outcomes confirm that the presented laser treatment method is an effective solution to correct fabrication defects, optimize conductor losses and provide high performance and reliable MIMO operation for future 5G communication systems. The novelty of this work comes from designing, implementing, and practically treating the antenna in a real setup.