Adaptive phase rotation of OFDM signals for PAPR reduction

High peak-to-average power ratio (PAPR) of the orthogonal frequency division multiplexing (OFDM) signal causes signal distortion, due to nonlinear high power amplifier at the transmitter, and affects received signal quality at the receiver. To reduce the PAPR, various PAPR reduction schemes have been developed. Of these schemes, the tone reservation (TR) scheme and the active constellation extension (ACE) scheme are used for commercial OFDM systems such as the DVB-T2 system. This paper presents an adaptive allpass filter (AAPF)-based PAPR reduction scheme. The AAPF scheme does not incur mean power increment and spectral efficiency decrement unlike the TR scheme. The AAPF scheme can be used with constellation rotation whereas the ACE scheme has a fundamental limitation with it. Comparison of the PAPR performance and the computational complexity with the TR scheme is made and discussed. Bit error rate (BER) performance demonstrates that adoption of the AAPF scheme does not affect signal reception quality at the receiver.^1.