The Experts below are selected from a list of 153 Experts worldwide ranked by ideXlab platform

Mingfu Tang - One of the best experts on this subject based on the ideXlab platform.

  • power allocation for Downlink Path based precoding in multiuser fdd massive mimo systems without csi feedback
    Asilomar Conference on Signals Systems and Computers, 2016
    Co-Authors: Chinwei Hsu, Mingfu Tang
    Abstract:

    In this paper, a Downlink Path-based precoding method for multiuser FDD massive MIMO systems is studied. Due to the huge feedback overhead of acquiring channel state information at the transmitter (CSI-T), FDD massive MIMO was usually considered impractical. In order to enhance the feasibility of such systems, a recent work proposed a precoding method without requiring CSI feedback by taking advantage of FDD reciprocity. Here, a power allocation scheme aimed at minimizing symbol error rate (SER) of each user is proposed for improving this method. Simulation results confirm that the proposed scheme improves the SER performance.

  • Downlink Path based precoding in fdd massive mimo systems without csi feedback
    Sensor Array and Multichannel Signal Processing Workshop, 2016
    Co-Authors: Mingfu Tang, Chihchi Chen
    Abstract:

    For a massive multiple-input-multiple-output (MIMO) system operated under frequency-division duplex (FDD), Downlink training was usually considered impractical due to huge amount of pilot signals and feedback overhead. Although some efforts have been spent to reduce such an overhead in recent works, the reduction is still limited. More recently, some precoding methods that do not require Downlink training and channel state information (CSI) feedback have been proposed by recognizing some similarity between uplink and Downlink channels. The base station may take advantage of such similarity and acquire partial knowledge of the Downlink channels using previous uplink channel estimates. In this paper, we propose to further exploit the diversity of a multiPath channel in a Downlink precoding method without CSI feedback. Specifically, space-time block code (STBC) is applied to enhance the robustness of Downlink transmission based on the partial CSI at the transmitter (CSI-T). Simulation results suggest that the proposed method achieves a competitive performance to other methods with only the partial CSI-T.

  • ACSSC - Power allocation for Downlink Path-based precoding in multiuser FDD massive MIMO systems without CSI feedback
    2016 50th Asilomar Conference on Signals Systems and Computers, 2016
    Co-Authors: Chinwei Hsu, Mingfu Tang
    Abstract:

    In this paper, a Downlink Path-based precoding method for multiuser FDD massive MIMO systems is studied. Due to the huge feedback overhead of acquiring channel state information at the transmitter (CSI-T), FDD massive MIMO was usually considered impractical. In order to enhance the feasibility of such systems, a recent work proposed a precoding method without requiring CSI feedback by taking advantage of FDD reciprocity. Here, a power allocation scheme aimed at minimizing symbol error rate (SER) of each user is proposed for improving this method. Simulation results confirm that the proposed scheme improves the SER performance.

  • SAM - Downlink Path-based precoding in FDD massive MIMO systems without CSI feedback
    2016 IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM), 2016
    Co-Authors: Mingfu Tang, Chihchi Chen
    Abstract:

    For a massive multiple-input-multiple-output (MIMO) system operated under frequency-division duplex (FDD), Downlink training was usually considered impractical due to huge amount of pilot signals and feedback overhead. Although some efforts have been spent to reduce such an overhead in recent works, the reduction is still limited. More recently, some precoding methods that do not require Downlink training and channel state information (CSI) feedback have been proposed by recognizing some similarity between uplink and Downlink channels. The base station may take advantage of such similarity and acquire partial knowledge of the Downlink channels using previous uplink channel estimates. In this paper, we propose to further exploit the diversity of a multiPath channel in a Downlink precoding method without CSI feedback. Specifically, space-time block code (STBC) is applied to enhance the robustness of Downlink transmission based on the partial CSI at the transmitter (CSI-T). Simulation results suggest that the proposed method achieves a competitive performance to other methods with only the partial CSI-T.

Jian-yu Wang - One of the best experts on this subject based on the ideXlab platform.

  • The effects of tilt corrected residual aberration on the detection probability of single-photon propagation in a slant Path turbulent atmosphere
    Optik, 2011
    Co-Authors: Jian-yu Wang, Yi-xin Zhang, Jianjun Jia, Yuanguang Wang
    Abstract:

    Abstract Based on the assumption of a pulse laser beam with an initial Gaussian temporal shape and a collimated fundamental-model Gaussian beam, the Rytov approximation and Kolmogorov spectrum model for the index-of-refraction fluctuation of atmosphere, the effect of turbulence on the probability density, acquisition transmittance probability, transmittance probability density, acquisition probability of single-photon propagation in atmospheric communication channel with z -tilt and centroid-tilt aberration corrected are studied theoretically. The probability density, acquisition transmittance probability, transmittance probability density and acquisition probability models for single-photon propagation in uplink Path and Downlink Path are derived. Our results shown that the detection probability and the acquisition transmittance probability of the single-photon are obvious increase, when the beams are propagation in the z -tilt corrected communication channel.

  • Detection Probability Model of Single Photons Propagation in a Slant Path Turbulent Atmosphere
    2010 Symposium on Photonics and Optoelectronics, 2010
    Co-Authors: Yi-xin Zhang, Jian-cai Xu, Jian-yu Wang
    Abstract:

    Based on the assumption of a pulse laser beam with an initial Gaussian temporal shape of the pulse and a Laguerre-Gaussian fundamental-model spatial distribution, the Rytov approximation and modified von Karman spectrum model of the index-of-refraction fluctuation of atmosphere, the effect of turbulence on the detection probability of single-photon propagation in atmospheric communication channel is studied theoretically. The detection probability models for single-photon propagation in uplink Path , the horizontal Path and Downlink Path are derived. The results show that the detection probabilities for photons in uplink/horizontal turbulent atmosphere channel are decreased as the Cn2 and propagation distance are increased. But, the detection probabilities of photons in Downlink turbulent atmosphere channel are independent on the Cn2(0) and the propagation distance effect also is weak.

Chinwei Hsu - One of the best experts on this subject based on the ideXlab platform.

  • power allocation for Downlink Path based precoding in multiuser fdd massive mimo systems without csi feedback
    Asilomar Conference on Signals Systems and Computers, 2016
    Co-Authors: Chinwei Hsu, Mingfu Tang
    Abstract:

    In this paper, a Downlink Path-based precoding method for multiuser FDD massive MIMO systems is studied. Due to the huge feedback overhead of acquiring channel state information at the transmitter (CSI-T), FDD massive MIMO was usually considered impractical. In order to enhance the feasibility of such systems, a recent work proposed a precoding method without requiring CSI feedback by taking advantage of FDD reciprocity. Here, a power allocation scheme aimed at minimizing symbol error rate (SER) of each user is proposed for improving this method. Simulation results confirm that the proposed scheme improves the SER performance.

  • ACSSC - Power allocation for Downlink Path-based precoding in multiuser FDD massive MIMO systems without CSI feedback
    2016 50th Asilomar Conference on Signals Systems and Computers, 2016
    Co-Authors: Chinwei Hsu, Mingfu Tang
    Abstract:

    In this paper, a Downlink Path-based precoding method for multiuser FDD massive MIMO systems is studied. Due to the huge feedback overhead of acquiring channel state information at the transmitter (CSI-T), FDD massive MIMO was usually considered impractical. In order to enhance the feasibility of such systems, a recent work proposed a precoding method without requiring CSI feedback by taking advantage of FDD reciprocity. Here, a power allocation scheme aimed at minimizing symbol error rate (SER) of each user is proposed for improving this method. Simulation results confirm that the proposed scheme improves the SER performance.

Yi-xin Zhang - One of the best experts on this subject based on the ideXlab platform.

  • The effects of tilt corrected residual aberration on the detection probability of single-photon propagation in a slant Path turbulent atmosphere
    Optik, 2011
    Co-Authors: Jian-yu Wang, Yi-xin Zhang, Jianjun Jia, Yuanguang Wang
    Abstract:

    Abstract Based on the assumption of a pulse laser beam with an initial Gaussian temporal shape and a collimated fundamental-model Gaussian beam, the Rytov approximation and Kolmogorov spectrum model for the index-of-refraction fluctuation of atmosphere, the effect of turbulence on the probability density, acquisition transmittance probability, transmittance probability density, acquisition probability of single-photon propagation in atmospheric communication channel with z -tilt and centroid-tilt aberration corrected are studied theoretically. The probability density, acquisition transmittance probability, transmittance probability density and acquisition probability models for single-photon propagation in uplink Path and Downlink Path are derived. Our results shown that the detection probability and the acquisition transmittance probability of the single-photon are obvious increase, when the beams are propagation in the z -tilt corrected communication channel.

  • Detection Probability Model of Single Photons Propagation in a Slant Path Turbulent Atmosphere
    2010 Symposium on Photonics and Optoelectronics, 2010
    Co-Authors: Yi-xin Zhang, Jian-cai Xu, Jian-yu Wang
    Abstract:

    Based on the assumption of a pulse laser beam with an initial Gaussian temporal shape of the pulse and a Laguerre-Gaussian fundamental-model spatial distribution, the Rytov approximation and modified von Karman spectrum model of the index-of-refraction fluctuation of atmosphere, the effect of turbulence on the detection probability of single-photon propagation in atmospheric communication channel is studied theoretically. The detection probability models for single-photon propagation in uplink Path , the horizontal Path and Downlink Path are derived. The results show that the detection probabilities for photons in uplink/horizontal turbulent atmosphere channel are decreased as the Cn2 and propagation distance are increased. But, the detection probabilities of photons in Downlink turbulent atmosphere channel are independent on the Cn2(0) and the propagation distance effect also is weak.

Chihchi Chen - One of the best experts on this subject based on the ideXlab platform.

  • Downlink Path based precoding in fdd massive mimo systems without csi feedback
    Sensor Array and Multichannel Signal Processing Workshop, 2016
    Co-Authors: Mingfu Tang, Chihchi Chen
    Abstract:

    For a massive multiple-input-multiple-output (MIMO) system operated under frequency-division duplex (FDD), Downlink training was usually considered impractical due to huge amount of pilot signals and feedback overhead. Although some efforts have been spent to reduce such an overhead in recent works, the reduction is still limited. More recently, some precoding methods that do not require Downlink training and channel state information (CSI) feedback have been proposed by recognizing some similarity between uplink and Downlink channels. The base station may take advantage of such similarity and acquire partial knowledge of the Downlink channels using previous uplink channel estimates. In this paper, we propose to further exploit the diversity of a multiPath channel in a Downlink precoding method without CSI feedback. Specifically, space-time block code (STBC) is applied to enhance the robustness of Downlink transmission based on the partial CSI at the transmitter (CSI-T). Simulation results suggest that the proposed method achieves a competitive performance to other methods with only the partial CSI-T.

  • SAM - Downlink Path-based precoding in FDD massive MIMO systems without CSI feedback
    2016 IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM), 2016
    Co-Authors: Mingfu Tang, Chihchi Chen
    Abstract:

    For a massive multiple-input-multiple-output (MIMO) system operated under frequency-division duplex (FDD), Downlink training was usually considered impractical due to huge amount of pilot signals and feedback overhead. Although some efforts have been spent to reduce such an overhead in recent works, the reduction is still limited. More recently, some precoding methods that do not require Downlink training and channel state information (CSI) feedback have been proposed by recognizing some similarity between uplink and Downlink channels. The base station may take advantage of such similarity and acquire partial knowledge of the Downlink channels using previous uplink channel estimates. In this paper, we propose to further exploit the diversity of a multiPath channel in a Downlink precoding method without CSI feedback. Specifically, space-time block code (STBC) is applied to enhance the robustness of Downlink transmission based on the partial CSI at the transmitter (CSI-T). Simulation results suggest that the proposed method achieves a competitive performance to other methods with only the partial CSI-T.