الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
FemtoceUs are low-power very small service area (e.g. home or office environment) cellular base stations, based on mobile technology, providing wireless voice and broadband services to customers in the home or office environment. Femtocells connect to the mobile operator’s network via a standard consumer broadband connection, including ADSL, cable or fiber. Data to and from the femtocell is carried over the Internet.
Femtocells will deliver data services to multiple users, typically at the full peak rate supported by the relevant air interface technology, currently several megabits per second and rising to tens and hundreds of megabits per second in the future.
Data from multiple femtocells are concentrated together in a gateway, managed by the mobile operator, and ultimately find their way back to the operator core network along with the data from the conventional operator macrocell network. The operator core network also contains a management system which provides services to the femtocell, ensuring that the services experienced by the user are secure, of high quality and can coexist with the signals from other femtocells and the outdoor network.
One of the most important open technical issues related to femtocells concerns the impact of femtocells on the performance of the conventional macro-cell system and the whole two-tier system. Interference management is an important consideration for femtocell deployment. The most effective sources of interference in downlink for the case of two tier L TE femtocell network working in closed subscriber groups are the Interference to the Macrocell UE Receiver (i.e. cross-tier interference) and the Interference to Nearby Femtocell UE Receivers (i.e. co-tier interference).
This thesis presents work done to address interference management in the context of down link LTE-FDD femtocell systems. It is proven that using closed access femtocells improves the overall performance of the network, but it shows some drawbacks as it decreases the performance of macro-cell mobile users neighboring to femto access points, and also reduces the performance of femto-cell mobile users connected to other femto access points. Some techniques are introduced to mitigate interference and to overcome these drawbacks,
Three techniques are proposed as solutions for the cross-tier interference; the use of path loss based power control, the use of fractional frequency reuse based resources allocation and the use of the use of beamforrning. And two techniques are also proposed as solutions for the co-tier interference; the use of femtocell self-configuration and auto resources allocation and the use of beamforrning.