Measurement-based antenna misalignment analysis and angle of arrival estimation for terahertz wireless communication systems

Abstract

As the demand for instant information and faster data transmission rates increases, the bandwidth requirements of wireless communication systems are predicted to exceed the capabilities of current millimeter-wave (mm-Wave) systems. To address this need, Terahertz (THz) wireless communication systems have emerged as a promising option for 6G and future wireless systems, offering a large contiguous bandwidth in the range of 0.1 THz - 10 THz that is applicable for both indoor and outdoor communication. However, the implementation of THz communication systems presents challenges due to substantial propagation losses, molecular absorption, and the effects of antenna misalignment on system performance. This master's thesis focuses on addressing the aforementioned challenges in THz communication systems. Our primary objective is to analyze the effects of antenna misalignment on system performance. To achieve this, we have designed and implemented a comprehensive measurement system capable of accurately characterizing the impact of misalignment on THz communication channels. By conducting extensive experiments and measurements, we aim to quantify the degradation in system performance caused by antenna misalignment and establish a thorough understanding of the underlying mechanisms. Furthermore, we aim to develop novel angle of arrival (AoA) estimation techniques specifically tailored for THz communication systems. These techniques will leverage advanced signal processing algorithms and innovative antenna array designs to accurately estimate the arrival angles of incoming signals, even in the presence of misalignment. By improving the accuracy of AoA estimation, we anticipate significant advancements in beamforming, spatial multiplexing, and other key aspects of THz system design. Through our research efforts, we strive to contribute to the development of more efficient and reliable THz wireless communication systems for future generations. By mitigating the impact of antenna misalignment and enhancing the accuracy of AoA estimation, we envision THz systems that can achieve higher data rates, improved coverage, and enhanced overall system performance. This work has the potential to revolutionize wireless communication and pave the way for the seamless integration of THz technology into various applications, including 6G networks, ultra-fast wireless links, and high-capacity communication systems. As a result, this master's thesis examines the potential of the THz band for wireless communication systems in the face of growing demand for data capacity in mobile networks. The study highlights the limitations of conventional frequency spectrums, such as the mm-Wave systems, and demonstrates how the THz band can overcome these limitations. The importance of comprehensive measurement campaigns and new algorithms to estimate the AoA and address antenna misalignment in THz wireless communication systems is emphasized. The thesis proposes a new algorithm, the AoSA-gold-MUSIC, which is designed specifically for THz-enabled space information networks (SINs) and is able to estimate AoA accurately while being computationally efficient. The analysis of channel impulse and frequency responses from the measurement campaign provides valuable insights into the behavior of electromagnetic waves in different scenarios and shows how the THz band could pave the way for next-generation wireless communication systems with disruptive metrics. These metrics include data rates of up to 100 Gbps, latency as low as 0.1 ms, and high spectrum efficiency.