Low-complexity PTS schemes using OFDM signal rotation and pre-exclusion of phase rotating vectors

• Published in: IET communications Vol. 10; no. 5; pp. 540 - 547
• Main Authors: Lee, Kang-Seok, Cho, Young-Jeon, Woo, Jun-Young, No, Jong-Seon, Shin, Dong-Joon
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 24.03.2016
• Subjects: Complexity; Computation; computational complexity; fast Fourier transforms; IFFT subblocks; inverse fast Fourier transformed subblocks; inverse transforms; low‐complexity PTS scheme; Mathematical analysis; OFDM modulation; OFDM signal rotation; OFDM signal vector; Orthogonal Frequency Division Multiplexing; orthogonal frequency division multiplexing systems; PAPR reduction scheme; partial transmit sequence; peak‐to‐average power ratio reduction scheme; phase rotating vectors; Reduction; Time domain; Time domain techniques; time‐domain analysis; time‐domain sample rotation; Vectors (mathematics); fast Fourier transforms; inverse fast Fourier transformed subblocks; peak-to-average power ratio reduction scheme; time-domain analysis; orthogonal frequency division multiplexing systems; low-complexity PTS scheme; time-domain sample rotation; inverse transforms; OFDM signal rotation; partial transmit sequence; PAPR reduction scheme; OFDM signal vector; IFFT subblocks; OFDM modulation; phase rotating vectors; computational complexity
• ISSN: 1751-8628; 1751-8636; 1751-8636
• DOI: 10.1049/iet-com.2015.0192

Partial transmit sequence (PTS), a well-known peak-to-average power ratio (PAPR) reduction scheme for orthogonal frequency division multiplexing (OFDM) systems, has been actively investigated to reduce its high computational complexity. Ku et al. proposed a selection method of dominant time-domain samples and by only using the selected samples, the PAPR of each alternative OFDM signal vector is calculated. This method clearly reduces the computational complexity but it is crucial to select proper time-domain samples to achieve acceptable PAPR reduction performance. In this study, a new selection method of dominant time-domain samples is proposed based on rotating samples of inverse fast Fourier transformed (IFFTed) subblocks to the local area on which the corresponding sample of the IFFTed first subblock is located. Moreover, pre-exclusion of phase rotating vectors based on the above time-domain sample rotation is proposed to further reduce the computational complexity. Numerical results confirm that the proposed PTS schemes substantially reduce the computational complexity with negligible degradation of PAPR reduction performance.