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Performance of LDPC Coded Spread OFDM With Clipping

Overview This paper presents the performance of OFDM systems with coding, spreading, and clipping. Low-Density Parity-Check (LDPC) codes give coding gains and spreading by the Walsh Hadamard transform gives gains in terms of increased frequency diversity as well as reduced Peak-to-Average Power Ratio (PAPR) of the transmitted OFDM signal. By evaluating both the IFFT transform (OFDM) and the Walsh Hadamard transform in a single step, the number of operations needed for the spread OFDM system is actually less than for the conventional OFDM system. Reducing the PAPR is important in systems with clipping since it is related to the probability of clips. Each clip introduces clipping noise to the system which reduces the performance.

Further White Paper Details
Publisher	University of Arizona	File Format	PDF
Date Published	May 2005	Downloads	2
Format	White Papers
Topics	Wireless LAN, Programming Languages, Mobile - Wireless Communications

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