1. Introduction to OFDM Fire Tom Wada Professor, Information Engineering, Univ. of the Ryukyus Chief Scientist at Magna Design Net, Inc [email_address] http://www.ie.u-ryukyu.ac.jp/~wada/ 06/07/09 System Arch 2007 (Fire Tom Wada)
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8. Symbol Waveform 06/07/09 System Arch 2007 (Fire Tom Wada) 1 0 1 0 0 Digital Information carrier ASK PSK FSK Symbol length
9. Multi bit modulation 06/07/09 System Arch 2007 (Fire Tom Wada) 1 0 1 0 0 carrier BPSK 1bit per symbol QPSK 2bit per symbol 10 11 01 00 01 Symbol length
17. Spectrum comparison for same data rate transmission 06/07/09 System Arch 2007 (Fire Tom Wada) frequency Single carrier frequency OFDM frequency Multi carrier
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22. Base-band OFDM signal 06/07/09 System Arch 2007 (Fire Tom Wada) T n=0 n=1 n=2 n=3 n=4 n=5 n=6 s B (t)
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25. Actual OFDM spectrum 06/07/09 System Arch 2007 (Fire Tom Wada) f c +kf 0 f c + ( k -1) f 0 f c + ( k +1) f 0
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29. OFDM modulator 06/07/09 System Arch 2007 (Fire Tom Wada) M A P S / P I-DFT P / S Real BPF generated 0 ~d N-1 AIR Bit stream Imag
30. OFDM demodulation 06/07/09 System Arch 2007 (Fire Tom Wada) d n = FFT(u(k))
31. OFDM demodulator (Too simple) 06/07/09 System Arch 2007 (Fire Tom Wada) T u n e r S / P DFT P / S A / D LPF Channel π/2 LPF D E M A P Bit Stream