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Hikmet Sari - One of the best experts on this subject based on the ideXlab platform.

  • a novel quasi orthogonal space frequency block code for single Carrier fdma
    Vehicular Technology Conference, 2008
    Co-Authors: Cristina Ciochina, Damien Castelain, D Mottier, Hikmet Sari
    Abstract:

    Single-Carrier frequency division multiple access (SC-FDMA) is a recent modulation technique combining most of the advantages of orthogonal frequency division multiple access (OFDMA) with the low peak-to-average power ratio (PAPR) of single-Carrier Transmission. For these reasons, it has been adopted as a possible air interface on the uplink of future wireless networks. It is also suitable for any other system in which a low PAPR is desired. In this paper, we highlight the severe limitations of existing space-time and space-frequency block codes when combined with SC-FDMA, and we propose a novel quasi-orthogonal space-frequency block code compatible with a SC-FDMA system with four transmit antennas. We show that our proposed preceding keeps the single-Carrier property of the signal on all of the four transmit antennas and we also prove the good performance of our scheme on frequency selective channels with spatial correlation.

  • Transmission techniques for digital terrestrial tv broadcasting
    IEEE Communications Magazine, 1995
    Co-Authors: Hikmet Sari, Georges Karam, I Jeanclaude
    Abstract:

    The authors discuss the potential of OFDM signaling, with its limitations and inherent problems, as well as another potential technique that has so far been overlooked: single-Carrier Transmission with frequency-domain equalization. The Carrier synchronisation issue is dealt with before the authors introduce coded-OFDM (COFDM), which makes use of channel coding and frequency-domain interleaving. >

  • an analysis of orthogonal frequency division multiplexing for mobile radio applications
    Vehicular Technology Conference, 1994
    Co-Authors: Hikmet Sari, Georges Karam, I Jeanclaude
    Abstract:

    Using static and time-varying channel impulse responses, the authors analyze the performance of orthogonal frequency-division multiplexing (OFDM) on multipath fading channels. They show that, provided it employs a frequency domain equalizer, single-Carrier Transmission substantially outperforms OFDM signalling, a result that contradicts the usual claims that OFDM signalling is more resistant to multipath fading than is standard single-Carrier Transmission. This finding is supported by computer simulation results and analytical arguments related to the decision process. The implication of the results is that not only OFDM signalling increases the system sensitivity to nonlinear distortion and Carrier synchronization errors, but it also turns out to offer no performance advantage on fading radio channels. >

  • frequency domain equalization of mobile radio and terrestrial broadcast channels
    Global Communications Conference, 1994
    Co-Authors: Hikmet Sari, Georges Karam, I Jeanclaud
    Abstract:

    For mobile radio and terrestrial broadcast applications, we compare orthogonal frequency-division multiplexing (OFDM) and single-Carrier Transmission with frequency-domain equalization. With respect to our earlier results, we include channel coding and frequency-domain interleaving which are necessary for OFDM systems on multipath fading channels characterized by deep notches in the signal spectrum. Our results indicate that a single-Carrier system with a frequency-domain equalizer achieves similar performance to coded-OFDM, while alleviating the Carrier synchronization and nonlinear distortion problems inherent to this technique.

Fumiyuki Adachi - One of the best experts on this subject based on the ideXlab platform.

  • mmse frequency domain equalization using spectrum combining for nyquist filtered broadband single Carrier Transmission
    Vehicular Technology Conference, 2010
    Co-Authors: Suguru Okuyama, Kazuki Takeda, Fumiyuki Adachi
    Abstract:

    Single Carrier (SC) signal Transmission has a property of low peak-to-average power ratio (PAPR) and achieves the frequency diversity gain by the use of frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion. In this paper, Nyquist filtered broadband SC Transmission is considered. As the transmit filter roll-off factor α increases, the signal bandwidth increases and the PAPR reduces. MMSE-FDE using spectrum combining was proposed in [15]. An additional frequency diversity gain can be obtained by making use of the excess bandwidth introduced by the transmit filter and by using spectrum combining. In this paper, we thoroughly investigate how α affects PAPR, BER performance, and throughput performance.

  • joint tomlinson harashima precoding and frequency domain equalization for broadband single Carrier Transmission
    IEICE Transactions on Communications, 2008
    Co-Authors: Kazuki Takeda, Hiromichi Tomeba, Fumiyuki Adachi
    Abstract:

    The performance of single-Carrier (SC) Transmission in a frequency-selective fading channel degrades due to a severe inter-symbol interference (ISI). Using frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion can improve the bit error rate (BER) performance of SC Transmission. However, the residual ISI after FDE limits the performance improvement. In this paper, we propose a joint use of Tomlinson-Harashima precoding (THP) and FDE to remove the residual ISI. An approximate conditional BER analysis is presented for the given channel condition. The achievable average BER performance is evaluated by Monte-Carlo numerical computation method using the derived conditional BER. The BER analysis is confirmed by computer simulation of the signal Transmission.

  • frequency domain space time block coded joint transmit receive diversity for the single Carrier Transmission
    International Conference on Conceptual Structures, 2006
    Co-Authors: Hiromichi Tomeba, Kazuaki Takeda, Fumiyuki Adachi
    Abstract:

    Recently, frequency-domain pre-equalization (pre-FDE) Transmission has been attracting attention for improving the broadband DS-CDMA (or single Carrier (SC)) Transmission performance in a frequency-selective fading channel. To further improve the Transmission performance, antenna diversity technique is very effective. However, so far the joint use of pre-FDE and the receive diversity has not been fully discussed. Recently, we proposed the space-time block coded-joint transmit/receive diversity (STBC-JTRD) for the narrow-band Transmission in a frequency-nonselective fading channel. STBC-JTRD allows an arbitrary number of transmit antennas while limiting the number of receive antennas to 4. In this paper, we extend the STBC-JTRD to the case of frequency-selective fading channel and propose the frequency-domain STBC-JTRD for the SC Transmission in a frequency-selective fading channel. The average bit error rate (BER) performance of the SC Transmission with frequency-domain STBC-JTRD is evaluated by the computer simulation.

Y Miyamoto - One of the best experts on this subject based on the ideXlab platform.

  • coherent optical single Carrier Transmission using overlap frequency domain equalization for long haul optical systems
    Journal of Lightwave Technology, 2009
    Co-Authors: Riichi Kudo, Koichi Ishihara, Y Takatori, Akihide Sano, Takayuki Kobayashi, Y Miyamoto
    Abstract:

    In this paper, we present coherent optical single Carrier Transmission (COSC) using overlap frequency domain equalization (OFDE) for the chromatic dispersion (CD) compensation. Residual inter-symbol interference is suppressed by time domain equalization with small tap size. In single polarization Transmission, 25-Gb/s COSC Transmission with OFDE is demonstrated over 800 km to 4320 km of single-mode fiber (SMF) without optical dispersion compensation. The measured results show that the proposed configuration improves the Transmission performance by setting adequate overlapped size of FFT windows and that it is suitable for long-haul optical communication systems.

  • single Carrier Transmission with two stage overlap frequency domain equalisation for long haul optical systems
    Electronics Letters, 2009
    Co-Authors: Riichi Kudo, Tetsuro Kobayashi, Koichi Ishihara, Y Takatori, Akihide Sano, E Yamada, H Masuda, Y Miyamoto, Masato Mizoguchi
    Abstract:

    Two-stage overlap frequency domain equalisation (OFDE) is proposed to compensate for chromatic dispersion and polarisation mode dispersion in practical long-haul optical systems. The Transmission performance of 25 Gbit/s coherent optical single Carrier Transmission (SC) with two-stage OFDE is evaluated. The results show that SC using two-stage OFDE attains the Q factor of 11.4 dB over 4320 km of singlemode fibre using 16-point FFT for demodulation.

  • pmd compensation in optical coherent single Carrier Transmission using frequency domain equalisation
    Electronics Letters, 2009
    Co-Authors: Riichi Kudo, Tetsuro Kobayashi, Koichi Ishihara, Y Takatori, Akihide Sano, E Yamada, H Masuda, Y Miyamoto
    Abstract:

    The Transmission performance of optical single-Carrier (SC) Transmission using frequency-domain equalisation (FDE) to counter polarisation mode dispersion (PMD) is evaluated. 25 Gbit/s coherent optical SC Transmission using FDE (CO-SC-FDE) is demonstrated in the presence of a significant amount of differential group delay (DGD). The results show that CO-SC-FDE compensates for the influence of the 125 ps DGD; the OSNR penalty is 0.81 dB.

I Jeanclaude - One of the best experts on this subject based on the ideXlab platform.

  • Transmission techniques for digital terrestrial tv broadcasting
    IEEE Communications Magazine, 1995
    Co-Authors: Hikmet Sari, Georges Karam, I Jeanclaude
    Abstract:

    The authors discuss the potential of OFDM signaling, with its limitations and inherent problems, as well as another potential technique that has so far been overlooked: single-Carrier Transmission with frequency-domain equalization. The Carrier synchronisation issue is dealt with before the authors introduce coded-OFDM (COFDM), which makes use of channel coding and frequency-domain interleaving. >

  • an analysis of orthogonal frequency division multiplexing for mobile radio applications
    Vehicular Technology Conference, 1994
    Co-Authors: Hikmet Sari, Georges Karam, I Jeanclaude
    Abstract:

    Using static and time-varying channel impulse responses, the authors analyze the performance of orthogonal frequency-division multiplexing (OFDM) on multipath fading channels. They show that, provided it employs a frequency domain equalizer, single-Carrier Transmission substantially outperforms OFDM signalling, a result that contradicts the usual claims that OFDM signalling is more resistant to multipath fading than is standard single-Carrier Transmission. This finding is supported by computer simulation results and analytical arguments related to the decision process. The implication of the results is that not only OFDM signalling increases the system sensitivity to nonlinear distortion and Carrier synchronization errors, but it also turns out to offer no performance advantage on fading radio channels. >

Riichi Kudo - One of the best experts on this subject based on the ideXlab platform.

  • coherent optical single Carrier Transmission using overlap frequency domain equalization for long haul optical systems
    Journal of Lightwave Technology, 2009
    Co-Authors: Riichi Kudo, Koichi Ishihara, Y Takatori, Akihide Sano, Takayuki Kobayashi, Y Miyamoto
    Abstract:

    In this paper, we present coherent optical single Carrier Transmission (COSC) using overlap frequency domain equalization (OFDE) for the chromatic dispersion (CD) compensation. Residual inter-symbol interference is suppressed by time domain equalization with small tap size. In single polarization Transmission, 25-Gb/s COSC Transmission with OFDE is demonstrated over 800 km to 4320 km of single-mode fiber (SMF) without optical dispersion compensation. The measured results show that the proposed configuration improves the Transmission performance by setting adequate overlapped size of FFT windows and that it is suitable for long-haul optical communication systems.

  • single Carrier Transmission with two stage overlap frequency domain equalisation for long haul optical systems
    Electronics Letters, 2009
    Co-Authors: Riichi Kudo, Tetsuro Kobayashi, Koichi Ishihara, Y Takatori, Akihide Sano, E Yamada, H Masuda, Y Miyamoto, Masato Mizoguchi
    Abstract:

    Two-stage overlap frequency domain equalisation (OFDE) is proposed to compensate for chromatic dispersion and polarisation mode dispersion in practical long-haul optical systems. The Transmission performance of 25 Gbit/s coherent optical single Carrier Transmission (SC) with two-stage OFDE is evaluated. The results show that SC using two-stage OFDE attains the Q factor of 11.4 dB over 4320 km of singlemode fibre using 16-point FFT for demodulation.

  • pmd compensation in optical coherent single Carrier Transmission using frequency domain equalisation
    Electronics Letters, 2009
    Co-Authors: Riichi Kudo, Tetsuro Kobayashi, Koichi Ishihara, Y Takatori, Akihide Sano, E Yamada, H Masuda, Y Miyamoto
    Abstract:

    The Transmission performance of optical single-Carrier (SC) Transmission using frequency-domain equalisation (FDE) to counter polarisation mode dispersion (PMD) is evaluated. 25 Gbit/s coherent optical SC Transmission using FDE (CO-SC-FDE) is demonstrated in the presence of a significant amount of differential group delay (DGD). The results show that CO-SC-FDE compensates for the influence of the 125 ps DGD; the OSNR penalty is 0.81 dB.