The Experts below are selected from a list of 15954 Experts worldwide ranked by ideXlab platform
Byonghyo Shim - One of the best experts on this subject based on the ideXlab platform.
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Packet Structure and Receiver Design for Low Latency Wireless Communications With Ultra-Short Packets
IEEE Transactions on Communications, 2018Co-Authors: Byungju Lee, David James Love, Hyoungju Ji, Sunho Park, Byonghyo ShimAbstract:Fifth generation wireless standards require much lower latency than what current wireless systems can guarantee. The main challenge in fulfilling these requirements is the development of short Packet transmission, in contrast to most of the current standards, which use a long data Packet Structure. Since the available training resources are limited by the Packet size, reliable channel and interference covariance estimation with reduced training overhead are crucial to any system using short data Packets. In this paper, we propose an efficient receiver that exploits useful information available in the data transmission period to enhance the reliability of the short Packet transmission. In the proposed method, the receive filter (i.e., the sample covariance matrix) is estimated using the received samples from the data transmission without using an interference training period. A channel estimation algorithm to use the most reliable data symbols as virtual pilots is employed to improve quality of the channel estimate. Simulation results verify that the proposed receiver algorithms enhance the reception quality of the short Packet transmission.
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Packet Structure and receiver design for low-latency communications with ultra-small Packets
2016 IEEE Global Communications Conference GLOBECOM 2016 - Proceedings, 2016Co-Authors: Byungju Lee, David James Love, Hyoungju Ji, Sunho Park, Byonghyo ShimAbstract:5G wireless standards require a much lower latency than what current wireless systems can guarantee. The main challenge to fulfill this requirement is the capability to support short Packet transmission, in contrast to most of the current standards which use a long data Packet Structure. In this paper, we propose an efficient receiver technique that exploits information obtained during the data transmission period to improve the reception quality of the short Packet transmission. Two key ingredients of the proposed method are 1) estimation of the receiver filter using the received samples in the data transmission period, not in the interference training period, and 2) soft decision- directed channel estimation that uses the data symbols for re-estimation of the channels. Numerical results confirm the effectiveness of the proposed receiver algorithms.
Elisabeth De Carvalho - One of the best experts on this subject based on the ideXlab platform.
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short Packet Structure for ultra reliable machine type communication tradeoff between detection and decoding
International Conference on Acoustics Speech and Signal Processing, 2018Co-Authors: Alexandrusabin Bana, Kasper Floe Trillingsgaard, Petar Popovski, Elisabeth De CarvalhoAbstract:Machine-type communication requires rethinking of the Structure of short Packets due to the coding limitations and the significant role of the control information. In ultra-reliable low-latency communication (URLLC), it is crucial to optimally use the limited degrees of freedom (DoFs) to send data and control information. We consider a URLLC model for short Packet transmission with acknow 1-edgement (ACK). We compare the detection/decoding performance of two short Packet Structures: (1) time-multiplexed detection sequence and data; and (2) Structure in which both Packet detection and data decoding use all DoFs. Specifically, as an instance of the second Structure we use superimposed sequences for detection and data. We derive the probabilities of false alarm and misdetection for an AWGN channel and numerically minimize the Packet error probability (PER), showing that for delay-constrained data and ACK exchange, there is a tradeoff between the resources spent for detection and decoding. We show that the optimal PER for the superimposed Structure is achieved for higher detection overhead. For this reason, the PER is also higher than in the preamble case. However, the superimposed Structure is advantageous due to its flexibility to achieve optimal operation without the need to use multiple codebooks.
Byungju Lee - One of the best experts on this subject based on the ideXlab platform.
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Packet Structure and Receiver Design for Low Latency Wireless Communications With Ultra-Short Packets
IEEE Transactions on Communications, 2018Co-Authors: Byungju Lee, David James Love, Hyoungju Ji, Sunho Park, Byonghyo ShimAbstract:Fifth generation wireless standards require much lower latency than what current wireless systems can guarantee. The main challenge in fulfilling these requirements is the development of short Packet transmission, in contrast to most of the current standards, which use a long data Packet Structure. Since the available training resources are limited by the Packet size, reliable channel and interference covariance estimation with reduced training overhead are crucial to any system using short data Packets. In this paper, we propose an efficient receiver that exploits useful information available in the data transmission period to enhance the reliability of the short Packet transmission. In the proposed method, the receive filter (i.e., the sample covariance matrix) is estimated using the received samples from the data transmission without using an interference training period. A channel estimation algorithm to use the most reliable data symbols as virtual pilots is employed to improve quality of the channel estimate. Simulation results verify that the proposed receiver algorithms enhance the reception quality of the short Packet transmission.
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Packet Structure and receiver design for low-latency communications with ultra-small Packets
2016 IEEE Global Communications Conference GLOBECOM 2016 - Proceedings, 2016Co-Authors: Byungju Lee, David James Love, Hyoungju Ji, Sunho Park, Byonghyo ShimAbstract:5G wireless standards require a much lower latency than what current wireless systems can guarantee. The main challenge to fulfill this requirement is the capability to support short Packet transmission, in contrast to most of the current standards which use a long data Packet Structure. In this paper, we propose an efficient receiver technique that exploits information obtained during the data transmission period to improve the reception quality of the short Packet transmission. Two key ingredients of the proposed method are 1) estimation of the receiver filter using the received samples in the data transmission period, not in the interference training period, and 2) soft decision- directed channel estimation that uses the data symbols for re-estimation of the channels. Numerical results confirm the effectiveness of the proposed receiver algorithms.
Alexandrusabin Bana - One of the best experts on this subject based on the ideXlab platform.
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short Packet Structure for ultra reliable machine type communication tradeoff between detection and decoding
International Conference on Acoustics Speech and Signal Processing, 2018Co-Authors: Alexandrusabin Bana, Kasper Floe Trillingsgaard, Petar Popovski, Elisabeth De CarvalhoAbstract:Machine-type communication requires rethinking of the Structure of short Packets due to the coding limitations and the significant role of the control information. In ultra-reliable low-latency communication (URLLC), it is crucial to optimally use the limited degrees of freedom (DoFs) to send data and control information. We consider a URLLC model for short Packet transmission with acknow 1-edgement (ACK). We compare the detection/decoding performance of two short Packet Structures: (1) time-multiplexed detection sequence and data; and (2) Structure in which both Packet detection and data decoding use all DoFs. Specifically, as an instance of the second Structure we use superimposed sequences for detection and data. We derive the probabilities of false alarm and misdetection for an AWGN channel and numerically minimize the Packet error probability (PER), showing that for delay-constrained data and ACK exchange, there is a tradeoff between the resources spent for detection and decoding. We show that the optimal PER for the superimposed Structure is achieved for higher detection overhead. For this reason, the PER is also higher than in the preamble case. However, the superimposed Structure is advantageous due to its flexibility to achieve optimal operation without the need to use multiple codebooks.
Pierre Duhamel - One of the best experts on this subject based on the ideXlab platform.
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Joint Exploitation of Residual Source Information and MAC Layer CRC Redundancy for Robust Video Decoding
2015Co-Authors: Khaled Bouchireb, Michel Kieffer, Senior Member, Pierre DuhamelAbstract:Abstract—This paper presents a MAP estimation method allowing the robust decoding of compressed video streams by exploiting the bitstream Structure (i.e., information about the source, related to variable-length codes and source character-istics) together with the knowledge of the MAC layer CRC (here considered as additional redundancy on the MAC Packet). This method is implemented via a sequential decoding algorithm in which the branch selection metric in the decoding trellis incorporates a CRC-dependent factor, and the paths which are not compatible with the source constraints are pruned. A first implementation of the proposed algorithm performs exact com-putations of the metrics, and is thus computationally expensive. Therefore, we also introduce a suboptimal (with tunable complex-ity) version of the proposed metric computation. This technique is then applied to the robust decoding of sequences encoded using the H.264/AVC standard based on CAVLC, and transmitted using a WiFi-like Packet Structure. Significant link budget improvement results are demonstrated for BPSK modulated signals sent over AWGN channels, even in the presence of channel coding. Index Terms—Communication systems, MAP estimation
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Joint Exploitation of Residual Source Information and MAC Layer CRC Redundancy for Robust Video Decoding
IEEE Transactions on Wireless Communications, 2010Co-Authors: Cedric Marin, Khaled Bouchireb, Michel Kieffer, Pierre DuhamelAbstract:This paper presents a MAP estimation method allowing the robust decoding of compressed video streams by exploiting the bitstream Structure (i.e., information about the source, related to variable-length codes and source characteristics) together with the knowledge of the MAC layer CRC (here considered as additional redundancy on the MAC Packet). This method is implemented via a sequential decoding algorithm in which the branch selection metric in the decoding trellis incorporates a CRC-dependent factor, and the paths which are not compatible with the source constraints are pruned. A first implementation of the proposed algorithm performs exact computations of the metrics, and is thus computationally expensive. Therefore, we also introduce a suboptimal (with tunable complexity) version of the proposed metric computation. This technique is then applied to the robust decoding of sequences encoded using the H.264/AVC standard based on CAVLC, and transmitted using aWiFi-like Packet Structure. Significant link budget improvement results are demonstrated for BPSK modulated signals sent over AWGN channels, even in the presence of channel coding.
