In the paper, the performance of quasi-synchronous
CDMA (QS-CDMA) system, which can allow an increased timing
error in synchronized access, is discussed. Average BER performance
of the system is analyzed in the condition of different access timing
error and different asynchronous users by simulation in AWGN
channel. The results show that QS-CDMA system is shown to have
great performance gain over the asynchronous system when access
timing error is within a few chips and asynchronous users is tolerable.
However, with access timing error increasing and asynchronous users
increasing, the performance of QS-CDMA will degrade. Also, we can
determine the number of tolerable asynchronous users for different
access timing error by simulation figures.
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