الفهرس 
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Abstract
The second generation for Terrestrial Digital Video Broadcasting (DVB-T2)
is planned to be applied in Egypt by 2015 as imposed by the International
Telecommunication Union (ITU). This new standard has many benefits over the
first generation (DVB-T) such as the newly adopted bandwidths, higher order
modulation schemes for better efficiency, the application of Rotated Q-Delayed
(RQD) modulation schemes that improve the Bit Error Rate (BER) performance
and the possibility of the Multiple Input Multiple Output (MIMO) transmission.
This thesis aims at introducing some enhancements in the DVB-T2 receiver.
Enhancements are mainly concerned with the BER improvement and the
Hardware (H/W) complexity reduction. Two subsystems were studied
thoroughly in this thesis, the Bit-Interleaved Coded Modulation (BICM) and
the MIMO-OFDM subsystems.
Regarding the BICM subsystem, the RQD scheme offers significant
improvement over unrotated modulation in terms of BER performance due to its
signal space diversity. In this thesis, we present five novel computationally
efficient demodulation schemes with hybrid soft-hard outputs used in hard
demapping of data. The presented schemes reduce the number of Log
Likelihood Ratio (LLR) computations. One proposed scheme gives the same
BER performance as traditional LLR while reducing the computational
complexity by 34% at SNR = 20 dB. Another scheme reduces the computations
by 25% independent of the SNR level. The other two schemes offer a tradeoff