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In a cellular mobile telephone system, when the electromagnetic
wave propagates in the channel , it undergoes several different
kinds of fading phenomenon under the influence of terrain and
buildings in the channel. In this thesis, we investigate the
performance of a digital cellular code division multiple access
system (CDMA). We consider the forward link transmission over a
channel which can be modeled as having a Rayleigh distribution
or a log-normal distribution. The worse case condition occurs
when the mobile is located in the intersection of three
neighboring cells, and the corresponding decoded bit error rate(
BER), namely the system performance, will be calculated. Error-
correction codes can be applied to lower this average bit error
rate. On the other hand, we investigate the employment of power
control to realize the improvement it makes on the system
perfomance.
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