Transmission Performance of Clipped and Filtered OFDM/TDM in A Frequency-selective Fading Channel

Abstract: Recently, we proposed OFDM combined with time division multiplexing (OFDM/TDM) to alleviate the high peak-to-average power ratio (PAPR) problem of OFDM. To further reduce the PAPR, amplitude clipping can be used. However, the bit error rate (BER) performance degrades and the out-of-band (OoB) power spectrum grows. Therefore, filtering is necessary to suppress the OoB power growth, but the PAPR will regrow. In this paper, by computer simulation, we study PAPR and OoB radiation trade-off of amplitude clipped and filtered OFDM/TDM. We discuss about how, and by how much, clipping affects the OFDM/TDM transmission in terms of PAPR, the power spectrum density (PSD) and the BER degradation. It is shown that OFDM/TDM can be used to reduce the clipping level and the required Eb/N0 for the given BER in comparison to OFDM with slight increase in OoB emission.