Navigating the Deluge_ Dubai Floods and the Resilience of Dubai International...
(Ofdm)
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