| Summary: | 碩士 === 國立交通大學 === 電子研究所 === 82 === In the TDMA cellular mobile communication, the received signal
may suffer from multipath fading due to the reflections of
buildings or terrain. An equalizer is needed to cancel the
intersymbol interference. We develop a C-language program to
simulate the North American IS-54 digital mobile system for the
equalizer design. A bi-directional equalization technique is
studied. The simulation result shows that it can solve the
divergence problem of the conventional DFE (Decision Feedback
Equalizer). We investigate the performance of the bi-
directional QRD-RLS DFE under different SNR, vehicle speed, and
delay spread. The finite-precision simulation results of the
QRD-RLS DFE are also discussed. A behavioral level circuit
simulation in Verilog HDL is accomplished as a verification.
Finally, we propose a low-complexity equalizer, which adopts
the LMS algorithm for tap-weight updating. A "multiple
training" scheme is used to overcome the bottleneck of slow
convergence of the LMS DFE.
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