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joint source-channel Bit Allocation Based on Expected End-to-End Distortion Model

Journal of Donghua University(English Edition) 2010年第4期27卷 458-462页

作者：马汉杰陈耀武 Institute of Advanced Digital Technology and Instrumentation Zhejiang University

An adaptive joint source channel bit allocation method for video communications over error-prone channel is *** protect the bit-streams from the channel bit errors,the rate compatible punctured convolution(RCPC)code is used to produce coding rates varying from 4/5 to 1/2 using the same encoder and the Viterbi *** expected end-to-end distortion model was presented to estimate the distortion introduced in compressed source coding due to quantization and channel bit errors *** on the proposed end-to-end distortion model,an adaptive joint source-channel bit allocation method was proposed under time-varying error-prone channel *** results show that the proposed methods could utilize the available channel capacity more efficiently and achieve better video quality than the other fixed coding-based bit allocation methods when transmitting over error-prone channels.

关键词： joint source-channel coding end-to-end distortion bit allocation rate compatible punctured convolution code

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Distortion Exponent in MIMO Fading channels With Time-Varying source Side Information

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IEEE TRANSACTIONS ON INFORMATION THEORY 2016年第6期62卷 3597-3617页

作者： Aguerri, Inaki Estella Gunduz, Deniz Imperial Coll London Dept Elect & Elect Engn London SW7 2BT England Huawei Technol Co Ltd France Res Ctr Math & Algorithm Sci Lab F-92100 Boulogne France Imperial Coll London Dept Elect & Elect Engn London SW7 2BT England

Transmission of a Gaussian source over a time-varying multiple-input multiple-output (MIMO) channel is studied under strict delay constraints. Availability of a correlated side information at the receiver is assumed, whose quality, i.e., its correlation with the source signal, also varies over time. A block-fading model is considered for the states of the time-varying channel and side information;perfect state information at the receiver is assumed, while the transmitter knows only the statistics. The high signal to noise ratio performance, characterized by the distortion exponent, is studied for this joint source-channel coding problem. An upper bound is derived and compared with several lower bounds based on list decoding (LD), hybrid digital-analog transmission, as well as multi-layer schemes, which transmit successive refinements of the source, relying on progressive or superposition transmission with LD. The optimal distortion exponent is characterized for the single-input multiple-output and multiple-input single-output scenarios by showing that the distortion exponent achieved by multi-layer superposition encoding with joint decoding meets the proposed upper bound. In the MIMO scenario, the optimal distortion exponent is characterized in the low bandwidth ratio regime, and it is shown that the multi-layer superposition encoding performs very close to the upper bound in the high bandwidth ratio regime.

关键词： Distortion exponent joint source-channel coding time-varying channel and side information list decoding broadcast codes successive refinement

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Compressed-and-Forward: Compressive Sensing for Cooperative Communication

Compressed-and-Forward: Compressive Sensing for Cooperative ...

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IEEE International Symposium on Intelligent Signal Processing and Communications Systems (ISPACS)

作者： Yeh, Chia-Hung Lin, Yu-Liang Liu, Cheng-Chih Huang, Wan-Jen Natl Sun Yat Sen Univ Dept Elect Engn Kaohsiung Taiwan Natl Sun Yat Sen Univ Inst Communicat Engn Kaohsiung Taiwan

ISBN: (纸本)9781467350839;9781467350815

Cooperative communication has been shown that it is an effective way to achieve spatial diversity in order to combat the user-outage caused by effects fading channel. Except for amplify-and-forward (AF) and decode-and-forward (DF), compressed-and-forward (CF) is also an efficient forwarding strategy. In the existing CF protocol, the relay will switch to the DF mode when the source transmitted signal can be recovered by the relay completely;however, no further compression is made in this scheme. This paper proposes a new CF scheme. The relay will estimate if the codeword in a predefined block can be succeeded decoded, then choose the corresponding forwarding methods which are based on joint source-channel coding or compressive sensing. At the decode side, a joint decoder is designed to decode the source according to the relay compression mode. Simulation results show that the proposed CF scheme can acquire the spatial diversity and outperform AF and DF schemes.

关键词： cooperative communication compressed-and-forward joint source-channel coding compressive sensing

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PACKET LOSS PROTECTION FOR INTERACTIVE AUDIO OBJECT RENDERING: A MULTIPLE DESCRIPTION APPROACH

PACKET LOSS PROTECTION FOR INTERACTIVE AUDIO OBJECT RENDERIN...

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4th International Workshop on Quality of Multimedia Experience (QoMEX)

作者： Zheng, Xiguang Ritz, Christian Univ Wollongong Sch Elect Comp & Telecommun Engn ICT Res Inst Wollongong NSW 2522 Australia

ISBN: (纸本)9781467307253

This paper presents a new framework for compression and transmission of simultaneously occurring audio objects through packet loss channels in order to maintain user Quality of Experience (QoE). The audio objects are compressed into two mono mixtures, by exploiting sparsity of multichannel audio signals to identify the two most dominant time-frequency components in terms of an energy measure. These mixtures are further compressed using the MP3 audio codec, with the optimised transmission model selected from several channel coding models based on the Forward Error Correction (FEC) and Multiple Description coding (MDC) packet loss protection techniques. Audio objects can be recovered robustly from any received description(s) allowing real-time selective reproduction at the listeners' end. Results from spectral distortion measurements indicate the proposed scheme maintains the perceptual quality of the audio objects across a wide variety of packet loss conditions.

关键词： Quality of Experience Audio Compression joint source-channel coding

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Deep Learning-Based Forward-Aware Quantization for Satellite-Aided Communications via Information Bottleneck Method

Deep Learning-Based Forward-Aware Quantization for Satellite...

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joint European Conference on Networks and Communications & 6G Summit (EuCNC/6G Summit)

作者： Hummert, Matthias Hassanpour, Shayan Wuebben, Dirk Dekorsy, Armin Univ Bremen Dept Commun Engn D-28359 Bremen Germany

ISBN: (纸本)9798350344998;9798350345001

We consider a two-hop transmission setup in the context of Non-Terrestrial Networks (NTNs). Explicitly, a noisy source signal should be compressed at an on-ground relay node before getting forwarded over an error-prone and rate-limited channel to a satellite transponder. The impacts of this imperfect forwarding should be integrated into the compressor's design formulation. In full harmony with the Information Bottleneck (IB) principle, we choose the Mutual Information (MI) as the fidelity criterion and devise a data-driven algorithm, the Deep Forward-Aware Vector Information Bottleneck (Deep FAVIB), to tackle the design problem, when solely a finite sample set is available. To this end, first we derive a tractable objective function and, later on, utilize it to train the encoder and decoder Deep Neural Networks (DNNs) in the introduced learning architecture. Our approach here, that is based on (generative) latent variable models, extends the well-known concepts of Variational Auto-Encoders (VAEs) and Deep Variational Information Bottleneck (Deep VIB) from remote source coding to joint source-channel coding. To corroborate the effectiveness of our data-driven approach, we also present several numerical results over a typical transmission scenario for NTNs.

关键词： 6G NTN deep learning information bottleneck joint source-channel coding variational auto-encoder

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Low-Complexity Hybrid Transceivers for Uplink Multiuser mmWave MIMO by User Clustering 27

Low-Complexity Hybrid Transceivers for Uplink Multiuser mmWa...

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27th European Signal Processing Conference (EUSIPCO)

作者： Perez-Adan, Darian Gonzalez-Coma, Jose P. Fresnedo, Oscar Castedo, Luis Univ A Coruna Dept Comp Engn CITIC La Coruna Spain

ISBN: (纸本)9789082797039

The high cost and power consumption of millimeter wave (mmWave) radio frequency (RF) hardware elements demands for advanced signal processing techniques to design MIMO transceivers. Hybrid analog-digital architectures for MIMO transceivers have become an attractive strategy to reduce the number of RF chains of the transceivers. In the uplink of a multiuser mmWave MIMO system, this hardware reduction is limited by the number of users to be handled, which can be rather large. In this work, we propose to use distributed quantizer linear coding (DQLC) in order to superimpose correlated sources in a cluster-based uplink multiuser mmWave MIMO system and reduce the number of RF chains at the receiver. The scheduling policy to cluster the transmitters is also analyzed by considering the correlation of the sources and channel state information (CSI). Numerical results show the advantage of employing the proposed scheme to reduce hardware complexity.

关键词： Millimeter wave joint source-channel coding uplink source correlation multiuser

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Trellis decoding for MPEG-4 streams over wireless channels

Trellis decoding for MPEG-4 streams over wireless channels

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Conference on Image and Video Communications and Processing

作者： Chen, QY Subbalakshmi, KP Stevens Inst Technol Dept Elect & Comp Engn Multimedia Syst Networking & Commun Lab Hoboken NJ 07030 USA

ISBN: (纸本)0819448222

Most video coding standards, including MPEG-4, use variable length codes to encode the discrete cosine transform (DCT) coefficients of intra. frames and inter frames, and the motion vector information. Although variable length codes can achieve good compression, they are very sensitive to channel errors, especially in Wireless channels, which are characterized by bursty errors. joint source-channel decoding (JSCD) is emerging as a potential alternative to traditional error resilience methods. for dealing with this sensitivity to channel errors. This paper describes one such JSCD for the reliable transmission of MPEG-4 video over wireless channels. We apply the maximum a posteriori probability based JSCD developed for first order Markov sources' to both inter and intra coded macroblocks. Experiments indicate that the proposed decoder gives significant improvements (9 dB in some cases) for MPEG-4 video with error resilience at various channel error rates.

关键词： multimedia over wireless networks MPEG-4 video over wireless channels joint source-channel coding error-resilient multimedia communication

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Design of VQ-based hybrid digital-analog joint source-channel codes for image communication

Design of VQ-based hybrid digital-analog joint source-channe...

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IEEE Data Compression Conference

作者： Wang, YD Alajaji, F Linder, T Queens Univ Dept Math & Stat Kingston ON K7L 3N6 Canada

ISBN: (纸本)0769523099

A joint source-channel coding system for image communication over an additive white Gaussian noise channel is presented. It employs vector quantization based hybrid, digital-analog modulation techniques with bandwidth compression and expansion for transmitting and reconstructing the wavelet coefficients of an image. The main advantage of the proposed system is that it achieves good performance at the design channel signal-to-noise ratio (CSNR), while still maintaining a "graceful improvement" characteristic at higher CSNRs. Comparisons are made with two purely digital systems and two purely analog systems. Simulation shows that the proposed system is superior to the other investigated systems for a wide range of CSNRs.

关键词： hybrid digital-analog coding joint source-channel coding vector quantization broadcasting robustness image coding discrete wavelet transform

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Phase Asynchronous Cognitive Interference channels: Lossless source-channel Separation Theorems

Phase Asynchronous Cognitive Interference Channels: Lossless...

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IEEE Global Communications Conference (GLOBECOM)

作者： Saffar, Hamidreza Ebrahimzadeh Mitran, Patrick Univ Waterloo Dept Elect & Comp Engn Waterloo ON N2L 3G1 Canada

ISBN: (纸本)9781467309219;9781467309202

Sufficient and necessary conditions for reliable lossless communication of two correlated sources over cIasses of phase asynchronous cognitive interference channels are derived. Namely, we consider interference channels in which one of the encoders, i.e., the secondary or cognitive user, is causally or non-causally aware of the other's message. Moreover, as a practical constraint, we assume the transmitters are not aware of the phase shirts introduced by channels. We show that, for both cIasses of causal and noncausal cooperation, under strong interference conditions, separate source and channel coding is optimal for reliable communication of both users. Also, we derive necessary and sufficient conditions for reliable communication of the cognitive radio transmission while the primary is able to maintain the same information rate it could reliably send in the absence of the secondary. To the best of our knowledge, this is the first work to find fundamental limits of lossless reliable communication for cognitive interference channels.

关键词： joint source-channel coding cognitive interference channel phase uncertainty correlated sources unidirectional cooperation

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Deep Learning Based Coded Over-the-Air Computation for Personalized Federated Learning 98

Deep Learning Based Coded Over-the-Air Computation for Perso...

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98th IEEE Vehicular Technology Conference (VTC-Fall)

作者： Chen, Danni Lei, Ming Zhao, Ming-Min Liu, An Sheng, Sikai Zhejiang Univ Coll Informat Sci & Elect Engn Hangzhou 310027 Peoples R China Zhejiang Prov Key Lab Informat Proc Commun & Netw Hangzhou 310027 Peoples R China

ISBN: (纸本)9798350329285

Federated learning (FL) is an edge learning framework that has received significant attention recently. However, the cost of communication has become a major challenge for FL as the number of edge devices grows and the complexity of training models increases. Besides, data samples across all edge devices are usually not independent and identically distributed (non-IID), posing additional challenges to the convergence and model accuracy of FL. Therefore, we propose a novel personalized FL framework based on deep coded over-the-air computation, named DipFL. In this framework, we design a deep AirComp aggregation (DACA) module for n-to-1 information aggregation. Besides, a joint source-channel coding (JSCC) module is designed based on the variational auto-encoder (VAE) model, which not only encodes the transmitted data, but also reduces the bias of local samples by introducing certain regularisation terms. In addition, we propose a personalized mix module that allows local models to be more personalized by mixing the global model and the local models. Simulation results confirm that the proposed DipFL framework is able to significantly reduce the amount of transmitted data, while improving FL performance especially at low signal-to-noise regimes.

关键词： Personalized federated learning over-the-air computation deep learning joint source-channel coding

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