Design of a Cloaked Dipole Antenna for a Multifunctional Aperture for 5G

Abstract

With the advent of 5G technology, there is a growing need for advanced antennas that can support multifunctional apertures efficiently and with minimal interference, especially at millimeter-wave (mmWave) frequencies. The thesis addresses this challenge by designing, simulating, and evaluating a cloaked dipole antenna designed for 5G applications.
The main concept of this work is a cloaking mechanism that reduces the scattering profile of the antenna at 28 GHz, improving its stealth characteristics. This allows the antenna to function at 3GHz without significantly affecting its efficiency or other operational characteristics. The scattering profile, measured as the antenna extinction cross-section, affects how much the antenna interferes with signals.
A special cloak was created using a capacitive metasurface to interact with the electromagnetic waves around the dipole antenna to achieve a reduction in electromagnetic scattering. This metasurface was engineered to eliminate the main scattering effects by inducing destructive interference between the scattered waves from the antenna and those generated by the metasurface itself. As a result, the electromagnetic footprint of the antenna is significantly reduced.
The design process involved creating and analyzing periodic unit cells, followed by optimizing the full antenna structure using FEKO simulation software. The simulation results demonstrated a significant peak reduction in the extinction cross-section of approximately
-7 dB at the cloaking frequency of 28 GHz. The bandwidth taken at -4 dB
extinction cross-section spans a frequency range from approximately 25.4 GHz to 29.4 GHz. This confirms the effectiveness of the cloaking mechanism in suppressing scattering.
Regarding the antenna’s performance at 3 GHz, the reflection coefficient showed a minimum value close to -24 dB, indicating efficient impedance matching and minimal signal reflection. This result suggests that the cloaking structures did not interfere significantly with the primary functionality of the antenna, although a slight retuning is required to
allow it to operate effectively within its designated frequency range.
These results highlight the potential of cloaking techniques to advance antenna design, making them more efficient and versatile for 5G and future technologies.
This research contributes to the field of antenna design and opens up new possibilities for developing sophisticated communication systems that prioritize multi-functionality and minimal interference.

Popular Abstract

In the rapidly evolving world of wireless communication, 5G technology is set to revolutionize the way we connect to the internet and each other. With promises of ultra-fast speeds, minimal delays, and the capacity to support millions of devices simultaneously, 5G is poised to drive future innovations—from smart cities and autonomous vehicles to immersive augmented reality experiences. However, realizing the full potential of 5G requires overcoming significant technical challenges, particularly in designing antennas that efficiently transmit and receive wireless signals in densely populated environments. While traditional antennas were effective in earlier communication systems, they often face bandwidth and interference management limitations, making them less ideal for the complex demands of 5G. This is where the concept of a "cloaked dipole antenna" becomes essential.
A dipole antenna is one of the simplest and most common types of antennas, which is
widely used in applications ranging from radio broadcasts to Wi-Fi routers. However, the high-performance requirements of 5G—such as increased bandwidth, higher data rates, and improved signal quality—demand antennas that can operate efficiently across a wider range of frequencies and provide greater directional gain. As a result, a basic dipole antenna may not suffice for these advanced applications, particularly at higher frequencies. To address these challenges, multifunctional apertures offer an innovative solution. These apertures are advanced antenna structures designed to support various roles at once, such as managing multiple frequency bands and different signal types to enhance performance characteristics like directional gain and signal quality essential for the diverse needs of 5G and other advanced communication systems.
This research focuses on designing a cloaked dipole antenna specifically optimized for a multifunctional aperture, which is a critical component in 5G networks. The design minimizes the Reflection Coefficient (S11) at 3 GHz so that the antenna can transmit and receive signals with minimal power loss, ensuring efficient energy use. At the higher frequency of 28 GHz, the design reduces the extinction cross-section, which minimizes energy losses due to scattering and absorption, leading to improved signal clarity in dense environments. Additionally, the antenna’s configuration mitigates interference, enhancing its effectiveness in crowded network settings where many devices are operating simultaneously.
The concept lies in the antenna’s ability to reduce its extinction cross-section, thereby minimizing energy losses due to scattering and absorption. This optimization allows the antenna to function more efficiently at 3 GHz, improving its performance for specific applications without interference from external signals. While the cloaked antenna doesn’t directly enhance connectivity or data rates, it increases operational efficiency by reducing energy loss, leading to more reliable performance in targeted scenarios. Furthermore, the multifunctional aperture’s versatility enables it to handle various tasks beyond simple signal transmission, including manipulating electromagnetic wave properties, making it
adaptable for different uses within the 5G spectrum.
The development of this cloaked dipole antenna represents a significant advancement for 5G infrastructure, particularly in base stations. By minimizing the Reflection Coefficient (S11) at 3 GHz, the antenna reduces power loss during transmission and reception, thereby improving signal efficiency. The cloaking mechanism at 28 GHz reduces scattering and absorption, minimizing interference from unwanted signal reflections and environmental factors. This optimized design ensures that the antenna operates efficiently across a broader range of frequencies, enhancing transmission quality and contributing to faster, more reliable data transfer. As 5G continues to expand, the demand for efficient, high-performance communication
networks, will grow rapidly. Innovations such as the cloaked dipole antenna for multifunctional apertures are critical in meeting these challenges. By providing a novel tool for improving antenna performance, this design facilitates effective operation across multiple frequency bands by reducing interference through its ability to minimize signal scattering and absorption. These advancements contribute to creating more reliable and robust communication systems in 5G networks.

• author: Oladimeji, Muyiwa Alfred
• supervisor: Alexandros Pallaris
• organization: Department of Electrical and Information Technology
• course: EITM02 20241
• year: 2024
• type: H2 - Master's Degree (Two Years)
• subject: Technology and Engineering
• keywords: Cloaked Dipole Antenna Multifunctional Aperture 5G Technology Electromagnetic Scattering Extinction Cross-Section Metasurface Cloaking Frequency Range 1 (FR1) Frequency Range 2 (FR2) FEKO Simulation Millimeter-Wave (mmWave) Frequencies Scattering Cancellation Reflection Coefficient Antenna Optimization
• report number: LU/LTH-EIT 2024-1024
• language: English
• id: 9176550
• date added to LUP: 2024-10-28 10:58:37
• date last changed: 2024-10-28 10:58:37