Enhancement In Reduction of PAPR using ASM based SFBC Technique in OFDM Systems

In this paper, we recommend Alternative-Signal Scheme for PAPR reduction in OFDM Systems with Space Frequency Block Coding (SFBC). The key idea of the proposed scheme is keeping the advantage of the SFBC structure to generate some multi-sequences via combining the OFDM signals at different transmit antennas. The OFDM is used to mitigate the problem of inter symbol interference (ISI) and provides good protection against co-channel interference and noise. One of the major drawbacks of in OFDM systems is that the transmitted signal exhibits a high PAPR when the input sequences are correlated. The space frequency block coding based Alternative-Signal schemes have been used to reduce peak to average power ratio (PAPR) orthogonal frequency division multiplexing (OFDM) system with space frequency block coding (SFBC). The Alternative-Signal scheme reduces the computational complexity and when Alternative-Signal scheme is used with quadrature amplitude modulation (QAM). Theoretical analysis and simulation results validate that the proposed scheme has the ability to provide large PAPR reduction, low bit error rate and low computational complexity without side information in SFBC MIMO-OFDM systems.