LEE- Telekomünikasyon Mühendisliği Lisansüstü Programı

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http://hdl.handle.net/11527/19468

Gözat

Yazar "Akca, Hüseyin" ile LEE- Telekomünikasyon Mühendisliği Lisansüstü Programı'a göz atma
  • Öge
    Power amplifer assisted ISAC
    (Graduate School, 2024-11-28) Akca, Hüseyin ; Çırpan, Hakan Ali ; 504191321 ; Telecommunication Engineering
    Integrated sensing and communication (ISAC) has emerged as a critical phenomenon for next-generation communication systems. Particularly, in the context of Institute of Electrical and Electronics Engineers (IEEE) standards and fifth-generation (5G) beyond standardization efforts, ISAC has established itself as a significant area of focus in both academia and industry. Given its importance to both the communication and radar communities, it is inevitable that research in the ISAC domain will continue to progress. Despite the similarities in the hardware of radar and communication systems, the two functions generally have distinct objectives. This distinction often results in trade-offs, as similar hardware components are used for different purposes with different waveform requirements. Addressing these trade-offs to enhance the joint performance of both functions introduces various challenges. This thesis focuses on the orthogonal frequency division multiplexing (OFDM) waveform. OFDM has already demonstrated its functionality in almost all communication standards and is expected to be indispensable in next-generation communication systems. Consequently, improving the performance of ISAC systems integrated with such networks necessitates optimizing their operation on the OFDM waveform. The first study examines the impact of radio frequency (RF) front-end components on ISAC Performance. The effects of RF front-end components, such as power amplifiers (PA), on communication performance are well-documented in the literature when using OFDM waveforms. Numerous studies have addressed the performance degradation caused by nonlinearities introduced by PAs. However, the impact of PA behaviour on sensing performance has received relatively little attention. This gap in the literature likely stems from the fact that traditional radar systems typically employ constant-envelope waveforms. Since OFDM lacks a constant-envelope structure, this study evaluates the influence of PA nonlinearities on sensing performance. To mitigate potential performance degradation, the study proposes extracting a PA model and incorporating it into the baseband reference signal. The second study takes into account an ISAC system employing OFDM waveforms, where the transmitter and receiver are distinct entities. The goal is to develop a more accurate channel estimation algorithm, impairment-aided channel state information (IA-CSI) that considers the distortions introduced by the PA. This approach aims to improve both sensing and communication performance. It is anticipated that ISAC-related research in both academia and industry will continue to accelerate, contributing to advancements in next-generation communication systems.