الفهرس 
Third Generation mobile communication systemsOnly 14 pages are availabe for public view
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Abstract
The primary goal of fourth generation (4G) wireless systems is
not only providing new technologies to cover the need for higher
data rates and new services, but also the integration of existing
technologies in a corrunon platform. Hence, the selection of a
generic air-interface for future generation wireless systems will be
of great importance. Although the exact requirements for 4G have
not yet been commonly defined, its new air interface will fulfill at
least some requirements such that it helps the 4G systems have a
generic architecture that enables the existing technologies to
integrate. It will use spectrum in an efficient manner and offer
higher data rates in a given spectrum. It will be also a highly
scalable system that enables the design of different cell
configurations (hot spot, cellular system). This provides better
coverage using software defined radio (SDR). Besides, it will be a
highly adaptive and reconfigurable system which can support
different standards and technologies. It is cost efficient which
makes marketing faster and offers future basis for new
technologies.
A new wireless communication system denoted as Orthogonal
Frequency Code Division Multiple Access (OFCDMA), which is
the combination of Orthogonal Frequency Division Multiplexing
(OFDM) and mean of two dimensional spreading namely time
domain and frequency domain spreading, IS analyzed in this
thesis.
The broadband OFCDMA becomes a very prorrusmg
technique to be used as multiple access technique for 4G high
speed wireless communications requirements due to its
advantages over OFDM as it has many degrees of freedom for
system adaptability and the spreading which has been offered to
OFDM to provide frequency diversity and facilitate one-cell
reuse.