PAPR analysis of superimposed training based MIMO-OFDM systems using an orthogonal affine precoder

Abstract

Precoder matrices are used in various contexts in the MIMO-OFDM systems. In particular, orthogonal affine precoder (OAP) is used in superimposed training (ST) based MIMO-OFDM system to nullify the data training interference. Precoders are also used to reduce the peak to average power ratio (PAPR) of MIMO-OFDM. In general, the OAP does not reduce the PAPR. In this paper a ZC based OAP is proposed that has lower PAPR compared to random OAPs. We also derive the distribution of PAPR considering ST based MIMO-OFDM systems which uses ZC based OAP and compare with the simulation results.