Arama Sonuçları

Listeleniyor 1 - 2 / 2
  • Yayın
    Performance analysis of space time transmit diversity in UMTS under presence of carrier phase offset
    (Işık Üniversitesi, 2003-12) Toplu, Mehmet İlker; Panayırcı, Erdal; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Elektronik Mühendisliği Yüksek Lisans Programı
    The reguirements for the next generation of mobile communication systems are primarily driven by the explosive growth of worldwide mobile communication subscribers. Additionaly, 3G systems will allow various of new services including wireless Internet acess, high -speed mobile data services and other multimedia applications. The expected growth of subscibers and the provided services indicate the need for increased system capacity of the future mobile communication systems. This thesis deals with Transmit Diversity techniques used for capacity enhancement in the downlink. The principle of Transmit Diversity is to send the same information with two antennas at the base station. If the signals from the different antennas fade independently, diversity at the receiver is achieved. Therefore, the ratio between the desired signal and the noise plus interference from other base stations can be enhanced. This means that there is less transmission power required to meet the same signal quality as in the single antenna case. The investigations within the scope of this work focus on Space-Time Transmit Diversity concept specified in the UMTS standard. I consider the application of Alamouti's Space-Time Transmit Diversity tevhniques in different scenarios. It's performance is evaluated by the calculation of the Average Error at the receiver depentent on the Signal to Noise Ratio. The performance of this method is compared by means MATLAB simulations.
  • Yayın
    Implementation of a fixed cellular terminal with mobile phone
    (Işık Üniversitesi, 2002-09) Tekeş, Coşkun; Yarman, Bekir Sıddık Binboğa; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Elektronik Mühendisliği Yüksek Lisans Programı
    The thesis reports the design and realization of a fixed cellular terminal (FCT) device which works with a mobile phone as a GSM Module. The design is emphasized at the structure not to be complex and suitable to be used in mass production. Before starting our design, our currently available FCT products and their functional properties are studied and the most important and usefull properties are fixed. This design is not only a theorical project, it is also realized as a mass product and take part in the market as a product.