Optimization of Random Phase Updating Technique for Effective Reduction in PAPR, Using Discrete Cosine Transform
: Pervasive computing
Babak Haji Bagher Naeeni
Orthogonal Frequency Division Multiplexing (OFDM)
Peak-to-Average Power Ratio (PAPR)
Random Phase Updating
Discrete Cosine Transform
One of problems of OFDM systems, is the big value of peak to average power ratio. To reduce it, any attempt have been done amongst which, random phase updating is an important technique. In contrast to paper, since power variance is computable before IFFT block, the complexity of this method would be less than other phase injection methods which could be an important factor. Another interesting capability of random phase updating technique is the possibility of applying the variance of threshold power. The operation of phase injection is repeated till the power variance reaches threshold power variance. However, this may be a considered as a disadvantage for random phase updating technique. The reason is that reaching the mentioned threshold may lead to possible system delay. In this paper, in order to solve the mentioned problem, DCT transform is applied on subcarrier outputs before phase injection. This leads to reduce the number of required carriers for reaching the threshold value which results in reducing system delay accordingly.
 V. K. Singh, A. Goel, A. Sharma. “Reducing Peak to Average Power Ratio of OFDM by Using Selective Mapping”. International Journal of Research in Information Technology, vol. 2.No.4, p-400-407, April 2014.
# T. Jiang and G. Zhu, “Complement block coding for reduction in peak to average power ratio of OFDM signals.” IEEE Radio Communications, vol. 43, no. 9, pp. s17-s22, Sept. 2005.
# Md. Ibhrahim Abdullah et.al, “Comparative Study of PAPR Reduction Techniques in OFDM”. ARPN journal of system and software, vol. 1, no. 8, pp. 263-269, nov 2011.
# P. Phoomchusak, C. Pirak, “Adaptive tone-reservation PAPR technique with optimal subcarriers allocation awareness for multi-user OFDMA systems.” 2011 the 13th International Conference on Advanced Communication Technology (ICACT), 2011.
# H. Chen, H. Liang. “Combined Selective Mapping and Binary Cyclic Codes for PAPR Reduction in OFDM Systems.” IEEE Transactions on Wireless Communications, vol.6, no.10, Oct. 2007.
 Nikookar, H., and Lidsheim, k.S.,“Random phase updating algorithm for OFDM transmission with low PAPR.” IEEE Transaction on Broadcasting, Vol.48, Jun 2002.
 H. Ochiai and H. Imai, “Performance of the deliberate clipping with symbol selection for strictly band-limited OFDM systems.” IEEE J. Sel. Areas Commun., vol. 18, no. 11, Nov. 2000.
 Jayalath, A., Tellambura, C., “Adaptive PTS approach for reduction of peak-to-average power ratio of OFDM signal.” Electronics Letters, Vol.36, No.14, pp. 1226-1228, 2000.
 S. Gazor, R. AliHemmati, “Tone reservation for OFDM systems by maximizing signalto-distortion ratio.” IEEE Transactions on Wireless Communications, 11(2), 2012.