Linear Precoding of OFDMA Signals to Minimize Their Instantaneous Power Variance

Is there an optimum linear block precoding for orthogonal frequency division multiple access (OFDMA) signals that significantly reduces their instantaneous power variance? We explore this question for linear block-precoded OFDMA signals with contiguous frequency mapping. We find that there is an optimum linear block precoding, but its advantage over DFT precoding (such as that used for the uplink signaling in the 3GPP-LTE standard) is rather small.