Master Degree / Yüksek Lisans Tezleri

Permanent URI for this collectionhttps://hdl.handle.net/11147/3008

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  • Master Thesis
    Interference Mitigation for Device-To Based Wireless Systems
    (Izmir Institute of Technology, 2018) Acar, Süleyman Onur; Özbek, Berna; Özbek, Berna; 03.05. Department of Electrical and Electronics Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Device-to-device (D2D) communication provides an effective way to meet growing mobile traffic and capacity demand. D2D communication can improve existing cellular systems in several ways. When UEs are located in close proximity, they can communicate through direct links bypassing the base station (BS). In this way, the transmitter consumes less power while better Quality-of-Service can still be provided. D2D links can also increase both energy and spectrum efficiency by reusing downlink and uplink cellular resources. However, integrating D2D links into the cellular infrastructure complicates the interference situation because D2D communication might increase the co-channel interference and degrade cellular link quality. In this thesis, the interference mitigation techniques including resource allocation, power control and multiple antenna are proposed for D2D communications underlaying cellular systems to increase the data rate of both the cellular users and D2D pairs. The Zero-Forcing technique is carried out for interference mitigation by assuming perfect channel state information at the BS side. The effect of a limited feedback link for downlink cellular communication and channel estimation for uplink communication are considered for underlying multi antenna cellular system.
  • Master Thesis
    Cell Selection Algorithms for Conventional Narrow Band Wireless Systems
    (Izmir Institute of Technology, 2017) Yılmaz, Saadet Simay; Özbek, Berna; Yılmaz, Saadet Simay; Özbek, Berna; 03.05. Department of Electrical and Electronics Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Public safety organizations provide a stable and secure environment for the society. Wireless communication between public safety officers is very important to transmit voice or data during an emergency crisis. When the public communication networks can not provide service during crisis, disaster and high traffic cases, Professional Mobile Radio systems (PMR) such as conventional Association of Public Safety Communications Officials (APCO25) and trunked Digital Mobile Radio (DMR) systems are needed to improve the service quality and to provide uninterrupted service provided to the users. While providing continuous voice and data service, it is very important to efficiently select the base station to be served and to ensure that a mobile user can seamlessly attach from one base station to another base station while moving within a cell. In this sense, it is critical to determine the base station to be served by efficient cell selection algorithms. Cell selection is the process of deciding the base station which provides services to the users. Cell selection plays an important role in balancing the system load and thus overall system performance. By means of efficient cell selection algorithms, it is aimed to reduce the waiting time and to connect a base station as soon as possible while establishing reliable transmission link for PMR systems in emergencies.