الفهرس 
Overview of DSL TechnologiesOnly 14 pages are availabe for public view
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Abstract
The Discrete Multi-Tone (DMT) modulation/demodulation scheme is the standard
physical-layer transmission technology in Asymmetric Digital Subscriber Line (ADSL) system.
At the DMT transceiver, channel equalization is carried out through a Time-domain Equalizer
(TEq) or a Frequency-domain Equalizer (FEq). The TEq is introduced to shorten the channel
response to a pre-defined length. On contrary, the FEq is used to compensate for the magnitude
and phase distortion caused by channel.
In this thesis, the Discrete Cosine Transform (DCT), along with its inverse can be used
instead of the Discrete Fourier Transform (DFT) along with its inverse in the DMT systems. The
results indicate that the proposed DCT-DMT system achieves a higher Signal to Noise Ratio
(SNR) in each sub-channel than the conventional DFT-DMT system with a Minimum Mean-
Squared Error time domain equalizer designed using the Unit-Tap Constraint (MMSE-UTC) over
the eight standard Carrier Serving Area (CSA). The major advantage of the DCT-DMT system is
the energy compaction property of the DCT. This property leaves most of the samples at the end
of each symbol close to zero, which reduces the Inter Symbol Interference (ISI), dramatically,
leading to a great performance enhancement.
The combined equalization approaches presented in this thesis yield higher data rates than
the decoupled approaches. So, the data rate can be maximized using the DCT with a combined
equalization approach. Simulation results have shown that the proposed DCT-DMT-TEq filter
bank system provides a better performance than the conventional DFT-DMT system. For low
complexity implementation, the Multi-carrier Equalization by Restoration of RedundancY
(MERRY) algorithm performs blind adaptive channel shortening for a multi-carrier signals with a
Cyclic Prefix (CP). The MERRY algorithm with the DCT approach gives better performance
than that of the DFT approach.