A Detailed Study of 4G in Wireless Communication: Looking Insight in Issues in OFDMAs a promising technique, OFDM has been widely used in emerging broadband communication systems, such as digital audio broadcasting (DAB), high-definition television (HDTV), and wireless local area network (IEEE 802.11a and HIPERLAN/2). However, as the OFDM signals are the sum of signals with random amplitude and phase, they are likely to have large PAPR that require a linear high-power- amplifier (HPA) with an extremely high dynamic range which is expensive and inefficient. Furthermore, any amplifier nonlinearity causes intermodulation products resulting in unwanted out-of-band power. A number of approaches have been proposed to deal with the PAPR problem, including amongst others, clipping, clipping-and-filtering (CF), coding, companding transform, active constellation extension (ACE), selected mapping (SLM), and partial transmit sequence (PTS). This book proposes an improvement in the selected mapping technique. The resulting scheme can also be applied to the multiple transmitting antenna cases. Further, it compares the simulation results to the existing techniques namely exponential companding transform, repeated clipping and filtering, and adaptive active constellation extension. |
Contents
CHAPTER 1 | 1 |
CHAPTER 2 | 20 |
CHAPTER 3 | 28 |
7Selected Mapping SLM | 35 |
CHAPTER5 | 47 |
CHAPTER6 | 58 |
CHAPTER 8 | 77 |
REFERENCES | 83 |
Other editions - View all
Common terms and phrases
3GPP Active Constellation Extension Adaptive Active Constellation Anti-Peak Signal AWGN bandwidth Bit Error Rate CCDF plot clipping and filtering clipping level Clipping-Based Active Constellation companding scheme Complimentary Cumulative Distribution Constellation Extension Adaptive Constellation Extension CB-ACE Cumulative Distribution Function cyclic prefix data block data rate Discrete Fourier Transform Distribution Function CCDF Division Multiple Access Division Multiplexing OFDM downlink Error Rate BER Exponential Companding Transform Extension Adaptive ACE Figure Frequency Division Multiplexing high PAPR IEEE input Interleaving ith iteration linear MATLAB multipath multiple access number of subcarriers OFDMA original OFDM signal original Orthogonal Frequency Orthogonal Frequency Division out-of-band PAPR reduction techniques peak signals Peak-to-Average Power Ratio Peak-to-Average Ratio power amplifier Power Ratio PAPR reduce the PAPR reducing the Peak-to-Average Repeated Clipping Riemann matrix SC-FDMA Selective Mapping SLM side information Signal-to-Noise Ratio Signal-to-Noise Ratio SNR single carrier SLM technique spectrum target clipping ratio transmission transmit signal uplink WiMAX Wireless