الفهرس 
chapter 1Only 14 pages are availabe for public view
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Abstract
OFDM is a promising technique for high rate transmission systems.
But, one major drawback or OFEM is the large Peak to Average
Power Ratio (PAPR) of the transmitted signal which reduces the
efficiency of transmitter power amplifier. The elimination of PAPR
can he achieved using Constant Envelope OFDM (CE-OFDM)
transformation technique at the expense of BER performance
degradation of the system which can be enhanced by adding a
Forward Error Correction (FEC). This paper studies the effect of the
inclusion of gray QAM mapper on the complexity and the BER
performance of CE-OFDM system with channel coding. It has been
demonstrated that the inclusion of gray QAM mapper instead of
conventional one reduces the receiver complexity of the channel
coded CE-OFDM system and greatly improve its BER performance,
specially, at low SNR region. A gain of more than 7.5dB is achieved
at a BER of l 0-4 over conventional CE-OFDM system when signal
transmit1cd over an A WGN channel, while it achieves a gain of more
than 8.5dB when signal transmitted over the multipath frequency selective fading channel.