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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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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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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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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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Error-resilient decoding of context-based adaptive binary arithmetic codes

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Signal, Image and Video Processing 2007年第1期1卷 77-87页

作者： Jeanne, Marion Guillemot, Christine Guionnet, Thomas Pauchet, Florelle IRISA INRIA Campus Universitaire de Beaulieu Rennes 35042 France Envivio Chantepie France

This paper addresses the problem of error-resilient decoding of bitstreams produced by the CABAC (context-based adaptive binary arithmetic coding) algorithm used in the H.264 video coding standard. The paper describes a maximum a posteriori (MAP) estimation algorithm improving the CABAC decoding performances in the presence of transmission errors. Methods improving the re-synchronization and error detection capabilities of the decoder are then described. A variant of the CABAC algorithm supporting error detection based on a forbidden interval is presented. The performances of the decoding algorithm are first assessed with theoretical sources and by considering different binarization codes. They are compared against those obtained with Exp-Golomb codes and with a transmission chain making use of an error-correcting code. The approach has been integrated in an H.264/MPEG-4 AVC video coder and decoder. The PSNR gains obtained are discussed. © 2007 Springer-Verlag London Limited.

关键词： Entropy coding Error resilience H.264/MPEG-4 AVC standard joint source-channel coding Video compression Wireless communication

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Adpative video transmission system over Rayleigh fading channel

Adpative video transmission system over Rayleigh fading chan...

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4th International Conference on Cybernetics and Information Technologies, Systems and Applications/5th Int Conf on Computing, Communications and Control Technologies

作者： Wu, Jia-Chyi Li, Chi-Min Huang, Wei-Chen Natl Taiwan Ocean Univ Dept Commun & Guidance Engn Chilung 20224 Taiwan

ISBN: (纸本)9781934272077

Objective of this paper is to investigate the joint source/channel coding and modulation algorithm, which provides a uniform video transmission rate to achieve better system performance with limited channel capacity. In the proposed algorithm we apply MPEG-2 video coding scheme, and turbo channel coding technique as well as BPSK/QPSK for modulation method. Rates assigned to MPEG-2 source coding and turbo channel coding schemes are based on the feedback information from Performance Control Unit (PCU) under system channel capacity limitation, which ensures the given system achieved the best performance compared to conventional systems.

关键词： joint source-channel coding MPEG2 turbo code Performance Control Unit (PCU)

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channels with cost constraints: strong converse and dispersion

Channels with cost constraints: strong converse and dispersi...

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IEEE International Symposium on Information Theory Proceedings (ISIT)

作者： Kostina, Victoria Verdu, Sergio Princeton Univ Dept Elect Engn Princeton NJ 08544 USA

ISBN: (纸本)9781479904464

This paper shows the strong converse and the dispersion of memoryless channels with cost constraints. The analysis is based on a new non-asymptotic converse bound expressed in terms of the distribution of a random variable termed the b-tilted information density, which plays a role similar to that of the information density in channel coding without cost constraints. We also analyze the fundamental limits of lossy joint-source-channel coding over channels with cost constraints.

关键词： Converse finite blocklength regime channels with cost constraints joint source-channel coding strong converse dispersion memoryless sources memoryless channels Shannon theory

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