A Modified Approach Based On SLM for OFDM PAPR Reduction Using Time Domain Sub-Block Conversion Matrix

OFDM is a digital transmission method developed to meet the increasing demand for higher data rates in communications which can be used in both wired and wireless environments. This paper describes the issue of the PAPR in OFDM which is a major drawback, and presents new and variations to existing algorithms to reduce it. The effect on system performance in terms of the BER and Power Spectral Density is simulated for an OFDM transceiver with a saturated High Power Amplifier. A modified SLM approach based on time-domain sub-block conversion matrices to reduce the computational complexity due to multiple IFFTs. This scheme is modified from the conversion matrix scheme. By dividing the frequency-domain signals into multiple sub-blocks, the number of the valid conversion matrices can be increased, and thus more candidate signals are available for PAPR reduction. By applying proposed scheme, the number of candidate signals can be increased from 12 in the original conversion matrix scheme to 28 and 128 for the two sub block and four-sub block cases, respectively. The scheme will provide improved PAPR reduction performance. In the same paper problem occurs due to the side information is also try to reduced. false side information detection degrades the bit error rate (BER) performance signi?cantly. In this paper, we propose a novel SLM scheme without any side information by devising phase rotation and simple scrambler detection in the receiver. DOI: 10.17762/ijritcc2321-8169.16043

A low-complexity peak-to-average power ratio reduction technique for OFDM systems

[[abstract]]© 2003 Institute of Electrical and Electronics Engineers - One major drawback of orthogonal frequency division multiplexing is the high peak-to-average power ratio (PAPR). The selective mapping (SLM) approach provides good performance for PAPR reduction, but it may suffer from the high computational complexity of the bank of inverse fast Fourier transforms (IFFTs). We propose two low-complexity conversions to replace half of the IFFTs in the SLM method. Computer simulation results and complexity analyses show that, with the two proposed conversions, we can reduce about half of the computational complexity of the SLM approach and get better performance for PAPR reduction.[[department]]電機工程學