Low-Complexity PAPR Reduction Scheme for Interleaved and Sub-Band OFDMA Uplink Systems
Both PAPR and computational complexity are critical challenges in OFDMA systems, especially for the mobile terminals. SLM schemes are commonly employed to reduce the PAPR in OFDM systems, but it requires many IFFT operations. In this paper, to decrease the number of IFFT operations and PAPR two methods are proposed. In first method, the candidate signals are generated in the time domain by linearly combining the original time-domain transmitted signal with multiple cyclic shift equivalents. In second method, training sequence is used. It is used to maintain the timing information between transmitter and receiver. By using the two methods the proposed architecture is proven to be applicable to OFDMA systems using either an interleaved or a sub-band sub-carrier assignment strategy.