Comparison of Constant Envelope and Peak Insertion Schemes for PAPR Reduction in a 6G Waveform

In this paper, we present a comparison between constant envelope (CE) and peak insertion (PI) schemes for the reduction of the peak-to-average power ratio (PAPR) in multicarrier signal orthogonal frequency division multiplexing with index modulation (OFDM-IM), that was proposed for the sixth-generation wireless networks (6 G). The parameters of the modulation index and the amplitude peak were evaluated, for maximum PAPR reduction, using simulations. A decrease of 7.6 dB is found for the constant envelope scheme for a index modulation of 0.1, which is 0.45 dB more than the peak insertion scheme when the gain of amplitude peak was 200. However, the latter requires a very high power increase over OFDM-IM to achieve this level of reduction. This makes the constant envelop scheme suitable for future green wireless networks.