Pilot Assignment Method for the PAPR Reduction and Effective Channel Estimation in the SC-FDMA Communication System

PAPR 감소와 효과적 채널 추정을 위한 SC-FDMA 통신 시스템의 파이럿 배치 방법

  • An, Dong-Geon (School of Electrical and Computer Engineering, Chungbuk National University) ;
  • Ryu, Heung-Gyoon (School of Electrical and Computer Engineering, Chungbuk National University)
  • 안동건 (충북대학교 전기전자컴퓨터공학부) ;
  • 유흥균 (충북대학교 전기전자컴퓨터공학부)
  • Published : 2010.01.31


PAPR of the pilot symbols can be reduced down by the CAZAC sequence in the SC-FDMA communication system. However, it is very complicated and takes quite a long time to compute the interpolation between the OFDM information symbols for the channel estimation because the pilot data are trasmitted in the block type. Furthermore, situation will be much more serious in the severe fading channel. Actually the pilot insertion of the comb type is much efficient and convenient for the channel estimation since the calculation of the interpolation can be made in the frequency domain symbol by symbol. But, the PAPR will be regrown when the pilot data are inserted with the information data in the comb type. So, in this paper, we like to study the PAPR reduction and comb type pilot assignment for the efficient channel estimation. Unlike the conventional SLM(selected mapping) method requiring the side information, our improved SLM method is to use the phase rotation sequence into information data without rotating phase of pilot. We use different pilot data according to the different phase rotation sequence. From the simulation result, it can be confirmed that when SLM method of 4 phase rotation sequence is used, PAPR is almost same to the block type method without pilot.


OFDM;CAZAC;SLM;PAPR;Pilot Allocation


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