Investigation of Compact Wideband MIMO Antennas with Enhanced Isolation on Diverse Substrates

Abstract

This thesis explores designing, developing, and optimizing compact wideband MIMO antennas using diverse substrate materials. It addresses critical challenges in enhancing isolation, bandwidth, diversity, and miniaturization. Through innovative antenna configurations, the research provides significant advancements for applications in WLAN, reconfigurable, wearable, and UWB systems. By exploring novel substrates alongside advanced MIMO configurations, this work highlights the transformative impact of material choice on antenna performance, specifically in reducing coupling and optimizing design efficiency. The following sections highlight the major contributions of each design presented in the thesis. The first segment of the research focuses on two compact wideband MIMO antenna designs using distinct substrates. The first design features a dual-port antenna built on an FR4 epoxy substrate, which offers simplicity in structure layout and broad bandwidth, covering WiMAX, WLAN, and C band downlink/uplink with excellent isolation, outstanding diversity performances, and stable time-domain characteristics, reaffirming the effectiveness of conventional materials for wideband MIMO systems. The second design, utilizing a non-conventional colored resin fiber substrate, forms a quad-port wideband MIMO antenna that spans an even broader frequency range, including WLAN, C-band uplink, downlink defense, and ITU bands, demonstrating superior isolation, time-domain characteristics, alongside excellent diversity performances. The novel use of this substrate showcases how non-conventional materials can elevate MIMO antenna performance by reducing coupling and optimizing overall functionality. newlineBuilding on the success of the wideband MIMO antenna designs, the thesis introduces an innovative compact dual-port reconfigurable MIMO antenna using a non-conventional colored resin fiber substrate, enabling switchable wide dual-band operation.