An Improved Selected Mapping Scheme for PAPR Reduction in OFDM Systems

Download or read book An Improved Selected Mapping Scheme for PAPR Reduction in OFDM Systems written by and published by . This book was released on 2006 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: Orthogonal Frequency Division Multiplexing (OFDM) is a spectrally efficient multicarrier modulation technique for high speed data transmission over multipath fading channels. High Peak-to-Average Power Ratio (PAPR), which leads to power inefficiency in the RF portion of the transmitter, is a major drawback of OFDM. Lots of PAPR reduction techniques are proposed in literatures in last two decades. For instance, amplitude clipping, companding, coding, partial transmit sequence, selected mapping (SLM), interleaving, etc. Among these techniques, SLM is a promising distortionless scheme to reduce PAPR. The major drawbacks of SLM are high complexity and the need to transmit side information. This thesis introduced an improved SLM scheme with a PAPR threshold. Mathematic expressions of Complementary Cumulative Distribution Function (CCDF) and expected number of mappings are derived and tested by computer simulations. The improved scheme has much lower computational complexity but keeps the same PAPR reduction performance comparing with traditional SLM technique.