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Communicating Linear Functions of Correlated Gaussian sources Over a MAC

IEEE TRANSACTIONS ON INFORMATION THEORY 2012年第3期58卷 1853-1860页

作者： Soundararajan, Rajiv Vishwanath, Sriram Univ Texas Austin Wireless Networking & Commun Grp Austin TX 78712 USA Univ Texas Austin Dept Elect & Comp Engn Austin TX 78712 USA

This paper considers the problem of transmitting linear functions of two correlated Gaussian sources over a two-user additive Gaussian noise multiple access channel. The goal is to recover this linear function within an average mean squared error distortion criterion. Each transmitter has access to only one of the two Gaussian sources and is limited by an average power constraint. In this paper, a lattice coding scheme and two lower bounds on the achievable distortion are presented. The lattice scheme achieves within a constant of a distortion lower bound if the signal-to-noise ratio is greater than a threshold. Furthermore, for the difference of correlated Gaussian sources, uncoded transmission is shown to be worse in performance to lattice coding methods for correlation coefficients above a threshold.

关键词： Distributed communication Gaussian multiple access channel (MAC) joint source channel coding lattice codes

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Structure-Preserving Hybrid Digital-Analog Video Delivery in Wireless Networks

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IEEE TRANSACTIONS ON MULTIMEDIA 2015年第9期17卷 1658-1670页

作者： He, Dongliang Luo, Chong Lan, Cuiling Wu, Feng Zeng, Wenjun Univ Sci & Technol China Hefei 230026 Peoples R China Microsoft Res Asia Beijing 100080 Peoples R China

Hybrid digital-analog (HDA) transmission has gained increasing attention recently in the context of wireless video delivery, for its ability to simultaneously achieve high transmission efficiency and smooth quality adaptation. However, previous systems are optimized solely based on the mean squared error criterion without taking the perceptual video quality into consideration. In this work, we propose a structure-preserving HDA video delivery system, named SharpCast, to improve both the objective and subjective visual quality. SharpCast decomposes a video into a content part and structure part. The latter is important to the human perception and therefore is protected with a robust digital transmission scheme. Then, the energy-intensive part in the content information is extracted and transmitted in digital for energy efficiency while the residual is transmitted in analog to achieve the desired smooth adaptation. We formulate the resource (power and bandwidth) allocation problem in SharpCast and solve the problem with a greedy strategy. Evaluations over nine standard 720p video sequences show that the proposed SharpCast system outperforms the state-of-the-art digital, analog, and HDA schemes by a notable margin in both peak signal-to-noise ratio (PSNR) and structural similarity (SSIM).

关键词： Hybrid digital-analog (HDA) joint source channel coding structural similarity wireless video delivery

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A combined multiple-candidate likelihood decoding and error concealment scheme for compressed video transmission over noisy channels

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2003年第10期18卷 971-980页

作者： Mei, Y Le-Ngoc, T Lynch, WE McGill Univ Dept Elect & Comp Engn Montreal PQ Canada Concordia Univ Dept Elect & Comp Engn Montreal PQ H3G 1M8 Canada

This paper presents a joint forward error correction (FEC) and error concealment (EC) scheme to enhance the quality of a compressed video signal transmitted over a noisy channel. A multiple candidate likelihood (MCL) channel decoding strategy is used in conjunction with redundancy in the compressed video (syntax validity and spatial discontinuity) to select the best-detected signal. Simulation results on both objective and subjective performance measures indicate a significant improvement provided by the proposed scheme. (C) 2003 Elsevier B.V. All rights reserved.

关键词： error concealment joint source channel coding combined error correction and error concealment likelihood decoding compressed video

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Designing a Common DP-LDPC Code Pair for Variable On-Body channels

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2022年第11期21卷 9596-9609页

作者： Song, Dan Ren, Jinkai Wang, Lin Chen, Guanrong Xiamen Univ Dept Informat & Commun Engn Xiamen 361005 Peoples R China City Univ Hong Kong Dept Elect Engn Hong Kong Peoples R China

The joint source channel coding (JSCC) system is sensitive to the changing channel characteristics, because the optimally designed source-channel code pair always needs to be redesigned when the transmission environment is updated. A solution is to seek a common code pair for variable channels. channel model 3 (CM3) is a variable on-body channel following the Weibull distribution, which is analyzed in four conditions due to varying shape factors, namely with exponential, Rayleigh, log-normal and normal distributions. The JSCC system is considered in this paper based on double protograph low-density parity-check (DP-LDPC) code pair over the variable CM3 channel. Firstly, four DP-LDPC code pairs are searched by the conventional differential evolution (DE) algorithm with four distributions of the Weibull model, respectively. However, these four code pairs only present good bit-error ratio performance in their own distribution, and have error floors in the other three. To resolve the problem, an artificial intelligence method based on principle component analysis (PCA) algorithm is designed to extract the common code pair. It is demonstrated that the common code pair performs well in noise-varying and practical-parameter transmissions. Instead of four DE code pairs, the designed one PCA code pair provides a strong technical support to low-complexity manufacturing such as eHealthcare.

关键词： Codes Wireless communication Encoding Body area networks Decoding Principal component analysis Parity check codes joint source channel coding optimal coding algorithm common DP-LDPC code pair wireless body area network principle component analysis

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Adaptive Bit Rate Control in Semantic Communication With Incremental Knowledge-Based HARQ

IEEE OPEN JOURNAL OF THE COMMUNICATIONS SOCIETY

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IEEE OPEN JOURNAL OF THE COMMUNICATIONS SOCIETY 2022年 3卷 1076-1089页

作者： Zhou, Qingyang Li, Rongpeng Zhao, Zhifeng Xiao, Yong Zhang, Honggang Zhejiang Univ Coll Informat Sci & Elect Engn Hangzhou 310027 Peoples R China Zhejiang Lab Hangzhou 311121 Peoples R China Huazhong Univ Sci & Technol Sch Elect Informat & Commun Wuhan 430074 Peoples R China Pengcheng Natl Lab Guangzhou Base Guangzhou 510555 Peoples R China

Semantic communication has witnessed a great progress with the development of natural language processing (NLP) and deep learning (DL). Although existing semantic communication technologies can effectively reduce errors in semantic interpretation, most of these solutions adopt a fixed bit length structure, along with a rigid transmission scheme, which is inefficient and lacks scalability faced with different meanings and signal-to-noise ratio (SNR) conditions. In this paper, we explore the impact of adaptive bit lengths on semantic coding (SC) under various channel conditions. First, we propose progressive semantic hybrid automatic repeat request (HARQ) schemes that utilize incremental knowledge (IK) to simultaneously reduce the communication cost and semantic error. On top of this, we design a novel semantic encoding solution with multi-bit length selection. In this fashion, the transmitter employs a policy network to decide the appropriate coding rate, so as to secure the correct information delivery at the cost of minimal bits. Moreover, a specific denoiser is further introduced to reduce the semantic errors encountered in the transmission process according to the semantic characteristics of context. Extensive simulation results have been conducted to verify the effectiveness of the proposed solution.

关键词： Semantics Decoding Encoding Bit rate Transformers Noise reduction channel coding Semantic communication semantic coding joint source channel coding deep learning neural network transformer end-to-end communication HARQ

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Combining Hidden Markov source Models and Parallel Concatenated Codes

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IEEE COMMUNICATIONS LETTERS 1997年第4期1卷 111-113页

作者： Garcia-Frias, Javier Villasenor, John D. Univ Calif Los Angeles Dept Elect Engn Los Angeles CA 90095 USA

We present here a framework for modifying a decoder for parallel concatenated codes to incorporate a general hidden Markov source model. This allows the receiver to utilize the statistical characteristics of the source during the decoding process, and leads to significantly improved performance relative to systems in which source statistics are not exploited. One of the constituent decoders makes use of a modified trellis which jointly describes the source and the encoder. The number of states in this modified trellis is the product of the number of states in the hidden Markov source and the number of states in the encoder.

关键词： Hidden Markov sources iterative decoding joint source channel coding turbo codes

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Robust image transmission using JPEG2000 and turbo-codes

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IEEE SIGNAL PROCESSING LETTERS 2002年第4期9卷 117-119页

作者： Banister, BA Belzer, B Fischer, TR Washington State Univ Sch Elect Engn & Comp Sci Pullman WA 99164 USA

A method of combined source and channel coding is described that provides robustness to errors from a binary symmetric channel and uses the JPEG2000 (JP2) image compression standard. The source code rate and channel code rate are jointly optimized to produce a stream of fixed-size channel packets, such that the rate allocation complexity grows O(N-2) with the number of transmitted packets, N. Punctured turbo codes are used for channel coding, providing strong error protection. The rate allocation scheme presented obtains all necessary information from the JP2 encoder, and does not require image decompression.

关键词： image coding joint source channel coding turbo code

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Hybrid symbol- and bit-based source-controlled channel decoding for MELP speech parameters

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IEEE COMMUNICATIONS LETTERS 2003年第8期7卷 394-396页

作者： Liu, XB Koh, SN Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore

A joint source channel coding (JSCC) scheme which exploits bit-level correlation as well as symbol-level correlation efficiently in a source-controlled channel decoding (SCCD) process is proposed and applied to the mixed-excitation linear prediction (MELP) parameters of speech. A modified BCJR algorithm is also proposed for use in the SCCD algorithm. Simulation results show that our proposed scheme performs better than other redundancy-based JSCC schemes such as bit-based SCCD, soft-bit speech decoding (SBSD) and iterative source-channel decoding.

关键词： joint source channel coding residual redundancy speech decoding

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joint source-channel Rate Allocation for Wireless Video Transmission Based on Distortion Estimation

Joint Source-Channel Rate Allocation for Wireless Video Tran...

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5th International Conference on Information Science and Applications (ICISA)

作者： dela Cruz, Angelo R. Cajote, Rhandley D. Univ Philippines Dept Elect & Elect Engn Quezon City 1101 Philippines

ISBN: (纸本)9781479944415

joint source channel coding provides an efficient framework in minimizing end-to-end distortion. In this paper, we propose a method of dynamically allocating the available bit rate between video encoder and channel encoder. The rate allocation algorithm is dependent on the estimated quantization and transmission distortion. We propose a quantization distortion model that is based on residual information and quantization parameter. Transmission distortion is estimated based on error propagation and error concealment distortion. Results show good estimate of the actual distortion and able to estimate the distortion before encoding the frame. The proposed distortion models are used to implement a joint source-channel video coding scheme using standard H.264/AVC encoder. The proposed scheme provides significant improvement in decoded video quality which can adapt to varying channel condition by proper allocation of available bit rate between video and channel encoder. The proposed distortion model can be extended in cross-layer optimization between channel encoder code rate and intra-refresh rate selection.

关键词： joint source channel coding quantization distortion transmission distortion error-control

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Combined source channel decoding for image transmission over fading channels 9

Combined source channel decoding for image transmission over...

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9th Asia-Pacific Conference on Communications held in conjunction with the 6th Malaysia International Conference on Communications (MICC 2003)

作者： Chebil, J Boashash, B Deriche, M Queensland Univ Technol Sch EESE Signal Proc Res Grp Brisbane Qld 4001 Australia

ISBN: (纸本)0780381149

Previous studies highlighted the importance of using residual redundancy techniques in the design of a joint source channel decoder for the case of data transmission over binary symmetrical channel. This paper uses the sequence maximum a posteriori (MAP) method, which is one of the residual redundancy techniques to design a joint source channel coding with the representation of the wireless communication channel by the Gilbert-Elliott channel (GEC). The paper also discusses the issue of parameters estimation for the GEC channel. A new modification is suggested to the Baum-Welch re-estimation technique in order to improve its performance and reduces its computational requirements.

关键词： joint source channel coding sequence maximum a posteriori Baum-Welch re-estimation techniques segmental k-means algorithm channel modeling Gilbert-Elliott channel

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