An energy efficient PAPR reduction technique for mobile terminals

An energy efficient PAPR reduction technique using adaptive clipping and filtering (CAF) for OFDM uplink transmission is proposed. Even though SC-FDMA is one of good choices for uplink transmission, there are several disadvantages which makes it less attractive to use in practical systems, such as high pilot overhead, link-level performance degradation, receiver complexity increment especially in MIMO mode, etc. There are various alternative PAPR reduction techniques to improve energy efficiency, and the CAF is the simplest and effective one, but oversampling and iteration requirements can be burdens. The proposed technique adaptively adjusts CR (Clipping Ratio) as a function of modulation, and has less burden of oversampling and iteration comparing with conventional Base Station (BS) CAF technique. Also, the effect of NI (Noise Interference) among users could be negligible owing to context-awareness and adaptive characteristics. Moreover it does not require receiver modification, thus improving energy efficiency of both BS and mobile terminals is possible. Simulation results show that the proposed technique presents excellent performance comparing with SC-FDMA.