Peak cancellation (PC) is known as one of the simplest peak-to-average power ratio (PAPR) reduction techniques that are applicable to various communications standards. The salient advantage of PC is its ease of hardware implementation, but it induces in-band distortion and out-of-band radiation. In order to restrict the amount of distortion within an acceptable level, it is critical to carefully design the cancelling pulses as well as the envelope threshold over which PC is applied. In most studies, however, they are determined empirically through computer simulations. This paper thus focuses on a rigorous theoretical analysis of PC applied to band-limited orthogonal frequency division multiplexing (OFDM) signals, and discusses its validity and limitation for practical applications. Based on the level-crossing rate approximation of the peak distribution, we derive a closed-form expression for the achievable signal-to-distortion power ratio (SDR). We also analyze the adjacent channel leakage ratio (ACLR) as well as error vector magnitude (EVM), with which the symbol error rate (SER) over an additive white Gaussian noise (AWGN) channel is obtained. All the theoretical results developed in this work are compared with those based on the corresponding computer simulations to justify our analytical approach. It thus serves as a useful and accurate tool for designing cancelling pulses as well as the threshold level, for given specific system requirements such as SDR (or EVM) and ACLR.
['Jiajia Song', 'Hideki Ochiai']
Performance Analysis for OFDM Signals With Peak Cancellation