• Title/Summary/Keyword: Partial Inverse Problem

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OFDM Communication System Using the Additive Control Tone for PAPR Reduction (PAPR 저감을 위하여 부가 Control 톤을 이용하는 OFDM 통신 시스템)

  • Kim Jin-Kwan;Lee Ill-Jin;Ryu Heung-Gyoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.12 s.103
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    • pp.1229-1238
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    • 2005
  • OFDM(Orthogonal Frequency Division Multiplexing) communications system is very attractive for the high data rate wireless transmission. However, it may be distorted in the nonlinear HPA(High Power Amplifier) since OFDM signal has hish PAPR(Peak-to-Average Power Ratio). In this paper, a new method using control tone is studied for reducing the PAPR and we call it PCT(PAPR Control Tone) method. This proposed PCT method is to assign control tones for PAPR reduction at the predefined sub-carriers. After IFFT(Inverse Fast Fourier Transform) and PAPR calculation, the OFDM data signal of the lowest PAPR is selected to transmit. Unlike the conventional method, it can cut down the computational complexity because it does not require the transmission and demodulation process of side information about the phase rotation. Furthermore, if this method is made up in parallel configuration, it can solve the time delay problem so that it can be processed in real time processing. This proposed method is compared with the conventional selected mapping(SLM) technique. We find out the PAPR reduction performance and BER when the number of control tone is 6 and nonlinear HPA is considered.