  Orthogonal frequency division multiplexing (OFDM) inherently suffers from two
major drawbacks: high out-of-band (OOB) power leakage and high peak-to-average
power ratio (PAPR). This paper proposes a novel approach called suppressing
alignment for the joint reduction of the OOB power leakage and PAPR. The
proposed approach exploits the temporal degrees of freedom provided by the
cyclic prefix(CP), a necessary redundancy in OFDM systems, to generate a
suppressing signal, that when added to the OFDM symbol, results in marked
reduction in both the OOB power leakage and PAPR. Additionally, and in order to
not cause any interference to the information data carried by the OFDM symbol,
the proposed approach utilizes the wireless channel to perfectly align the
suppressing signal with the CP duration at the OFDM receiver. Essentially,
maintaining a bit error rate (BER) performance similar to legacy OFDM without
requiring any change in the receiver structure.
