الفهرس 
History of MIMO Antenna SystemsOnly 14 pages are availabe for public view
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Abstract
Multiple-Input-Multiple-Output (MIMO) antenna technology refers to an advanced antenna configuration featuring multiple radiators at both the transmitter and receiver ends. This technology’s primary aim is to enhance data transmission rates in wireless communication systems by enabling multiple data streams to share the same bandwidth, particularly in challenging multipath environments. However, a significant challenge inherent to MIMO technology is the coupling that can occur between these radiating elements. When coupling is significant, the MIMO antenna system effectively behaves more like an antenna array than a true MIMO system. Thus, achieving robust decoupling between the radiating elements is essential to fully harness the potential benefits of MIMO technology. To address these challenges and advance the field of 5G communication, this thesis sets out to investigate and implement various printed MIMO antenna designs that incorporate innovative decoupling techniques. These designs are tailored specifically for 5G applications, which demand high data rates and reliable connectivity. The performance of these MIMO antenna systems will be evaluated through a comprehensive analysis, including the examination of scattering parameters, envelope correlation coefficient (ECC), antenna efficiency, antenna gain, and antenna radiation patterns. This research aims to contribute valuable insights into optimizing MIMO technology for the evolving landscape of wireless communication in the 5G era.
Four proposed antennas are designed for both single and dual-band operation, constitute the core of this MIMO system. This configuration employs four combining antenna elements, enabling it to function across single and two distinct frequency bands. Specifically, it covers frequencies of 3.65 GHz, 30 GHz and 31 GHz, offering a substantial bandwidth of approximately 7 GHz. Such versatile operation positions it effectively for applications involving millimeter waves, including the fifth generation (5G) wireless communication systems and the anticipated sixth generation (6G) communication technology. Upon conducting simulations of the MIMO antenna, it became evident that mutual coupling between the ports presented a challenge. To mitigate this issue and enhance the mutual coupling values, various techniques were employed, including the implementation of Curved Edges (CE), Defected Ground Structure (DGS) and Band Gap Structure (BGS). Remarkably, these techniques, whether used individually or in combination, had a positive impact on improving the mutual coupling values. Consequently, these single and dual-band MIMO antennas are well-equipped to cater to the demands of smart devices operating within 5G applications.
In pursuit of validating the simulated results, both a single band antenna and a dual-band MIMO antenna were fabricated and subjected to performance measurements. The outcomes of these real-world tests exhibited a strong correlation with the simulated results, affirming the effectiveness and reliability of the designed MIMO antenna system.