Modified tone reservation for PAPR reduction in OFDM systems

Abstract

One of the main drawbacks of orthogonal frequency division multiplex modulation is its high peak-to-average power ratio (PAPR) which can induce poor power efficiency at high power amplifier. Tone reservation (TR) is the most popular PAPR mitigation technique that uses a set of reserved tones to design peak cancelling signal for PAPR reduction. Finding an effective peak cancelling for PAPR reduction in the time domain by using only a small number of reserved tones, is not straightforward. Therefore, we are led to a trade-off between computational complexity and PAPR reduction. The TR method based on the gradient projection algorithm gives the best compromise. In this paper, we propose to modify the classical TR structure. The new proposed method achieves an improvement up to 1.2 dB in terms of PAPR performance without increasing the complexity. The effectiveness of this solution is confirmed through theoretical analysis and simulation results.