Optimal rate and power allocation algorithm in tdd-ofdm based two-tier femtocell networks
Tez Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Kadir Has Üniversitesi, Mühendislik ve Doğa Bilimleri Fakültesi, Elektrik Elektronik Mühendisliği, Türkiye
Tez Danışmanı: Erdal Panayirci
Tezin Onay Tarihi: 2014
Tezin Dili: İngilizce
Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
Özet:
People nowadays are witnessing the acceleration of development of electronics. The new technologies of electronic devices has made mobile phones smarter and more technologically advanced, where they support software platforms and applications that increased the demands on high data rates and gives the users the ability to play online games, video chat, upload-download data, and watch videos on social networks and other video-streaming websites. According to statistics of researches and telecommunication companies, the average usage area of a mobile data transfer users are generated from indoor places e.g. houses. Mobile operators seeks out for providing high data rates to increase their capacity to suit the demands of indoor users for those who experience weak signal power; However, the current studies suggests a distance decreasing between the Mobile Station (MS) and Base Station (BS) for a lower distance of wireless communication. Femtocell technology, also called Home Base Station (HBS), provides a high data transfer rates and better coverage area for limited number of indoor users, where the conventional base station used by the telecommunication company that has a wide coverage correspondingly named Macro Base Station (MBS). In home base station technology, the femtocell users uses the same spectrum for uplink and downlink frequencies that the other mobile stations are using for communication with the MBS. However, for such a communication system, it brings out a new area for research regarding interference management. In this thesis, an adaptive power control algorithm based on the network’s present parameters with two constraints performed at the femtocell users’ uplink channels for interference mitigation in a Time Division Duplex-Orthogonal Frequency Division Multiplexing (TDD-OFDM) wireless communication fashion. The constraints aims to ensure the quality of service of communication of MBS’s user and to preserve the data rate of femtocell users from collapsing. The first constraint is regarding the mitigation of the interference coming from the femtocell user to the macro mobile station; this constraint depends on the availability of the time slot that both femtocell and macrocell users are sharing subject to a certain frequency. The second constraint is regarding the limitation of the femtocell user’s transmitting power based on the maximization of the weighted rate sum of the femtocell users subject to the power summation of each femtocell user on each subchannel. Accordingly, we study the scenarios that considers both the cross-tier and co-tier interferences to mimic the realistic femtocell environment.