Analysis Of Tone Reservation Based Papr Reduction Methods In OQAM-OFDM System

The orthogonal frequency division multiplexing based on offset quadrature amplitudemodulation (OQAM-OFDM) system is now a recognized alternative to the conventionalOFDM system for the data transmission over multipath fading channels. However, theOQAM-OFDM system still has some challenging issues to be resolved. One criticaltechnical problem is the fast implementation of the OQAMOFDM system. Meanwhile, theOQAM-OFDM system suffers from the high peak-to-average power ratio (PAPR)problem that is inherent to the multicarrier modulations (MCM).In this paper, we first propose a simple inverse fast Fourier transform/fast Fouriertransform (IFFT/FFT) based implementation scheme of the OQAM-OFDM system. Then,with the fast implementation framework, the overlapped scaling tone reservation (OS-TR)and the multikernel tone reservation (MK-TR) methods are proposed to reduce the PAPRof the OQAM-OFDM signals.Since adjacent data blocks in the time domain overlap with each other due to theintroduction of the filter bank, the OS-TR method scales the filtered clipping noise togenerate the peak-canceling signal, and all the influences of the associated overlaps aretaken into account when computing the scaling factors. The OS-TR method could achievea good trade-off between the PAPR reduction and the computational complexity.The MK-TR method utilizes multiple impulse-like time domain kernels subject to theTR constraints to eliminate the high peaks of the OQAM-OFDM signal. Since theOQAM-OFDM system is more complex than the conventional OFDM system, the timedomain kernel of the OQAM-OFDM system is different from that of the conventionalOFDM system. Compared with the OS-TR method, the MK-TR method is more targetedon eliminating peaks, resulting in a better PAPR reduction performance.