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Full-featured, error-resilient, scalable wavelet video codec based on the set partitioning in hierarchical trees (SPIHT) algorithm

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2002年第3期12卷 157-171页

作者： Cho, S Pearlman, WA Rensselaer Polytech Inst Ctr Next Generat Video Res Dept Elect Comp & Syst Engn Troy NY 12180 USA Rensselaer Polytech Inst Ctr Image Proc Res Troy NY 12180 USA

Compressed video bitstreams require protection from channel errors in a wireless channel. The 3-D set partitioning in hierarchical trees (SPIHT) coder has proved its efficiency and its real-time capability in compression of video. A forward-error-correcting (FEC) channel (RCPC) code combined with a single automatic-repeat request (ARQ) proved to be an effective means for protecting the bitstream. There were two problems with this scheme: 1) the noiseless reverse channel ARQ may not be feasible in practice and 2) in the absence of channel coding and ARQ, the decoded sequence was hopelessly corrupted even for relatively clean channels. In this paper, we eliminate the need for ARQ by making the 3-D SPIHT bitstream more robust and resistant to channel errors. We first break the wavelet transform into a number of spatio-temporal tree blocks which can be encoded and decoded independently by the 3-D SPIHT algorithm. This procedure brings the added benefit of parallelization of the compression and decompression algorithms, and enables implementation of region-based coding. We demonstrate the packetization of the bitstream and the reorganization of these packets to achieve scalability in bit rate and/or resolution in addition to robustness. Then we encode each packet with a channel code. Not only does this protect the integrity of the packets in most cases, but it also allows detection of packet-decoding failures, so that only the cleanly recovered packets are reconstructed. In extensive comparative tests, the reconstructed video is shown to be superior to that of MPEG-2, with the margin of superiority growing substantially as the channel becomes noisier. Furthermore, the parallelization makes possible real-time implementation in hardware and software.

关键词： 3-D wavelet transform combined source-channel coding embedded wavelet coding error-resilient transmission robust source coding video compression video transmission

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JOINT DESIGN OF BLOCK source CODES AND MODULATION SIGNAL SETS

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IEEE TRANSACTIONS ON INFORMATION THEORY 1992年第4期38卷 1230-1248页

作者： VAISHAMPAYAN, VA FARVARDIN, N UNIV MARYLAND DEPT ELECT ENGN COLLEGE PK MD 20742 USA

The problem of designing a bandwidth-efficient, average-power-limited digital communication system for transmitting information from a source with known statistics over a noisy waveform channel is considered. Each output vector of the source is encoded by a block encoder to one of a finite number of signals in a modulation signal set. The received waveform is processed in the receiver by an estimation-based decoder. The goal is to design an encoder, decoder, and modulation signal set to minimize the mean squared error (mse) between the source vector and its estimate in the receiver. For a linear decoder, we derive necessary conditions for optimality of the encoder, decoder and the signal set and develop a convergent algorithm for solving these necessary conditions. We prove that the mse of the digital system designed here is bounded from below by the mse of an analog modulation system. Performance results for the digital system and signal constellation designs are presented for first-order Gauss-Markov sources and a white Gaussian channel. Comparisons are made against a standard vector quantizer (VQ)-based system, the bounding analog modulation system and the optimum performance theoretically attainable. The results indicate that for a correlated source, a sufficiently noisy channel and specific source block sizes and bandwidths, the digital system performance coincides with the optimum performance theoretically attainable. Further, significant performance improvements over the standard VQ-based system are demonstrated when the channel is noisy. Situations in which the linearity assumption results in poor performance are also identified.

关键词： combined source-channel coding VECTOR QUANTIZATION SIGNAL DESIGN

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Soft-decoding vector quantizer using reliability information from turbo-codes

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IEEE COMMUNICATIONS LETTERS 1999年第7期3卷 208-210页

作者： Ho, KP Department of Information Engineering Chinese University of Hong Kong Sha Tin Hong Kong China

The optimum soft-decoding vector quantizer using the reliability information from Turbo-codes is derived for combined source-channel coding. The encoder and decoder of the quantizer are optimized iteratively. For a four-dimensional vector quantizer having a rate of 1 bit/sample transmitted through a noisy channel, the soft-decoding channel-optimized quantizer can achieve about 3-3.7 dB performance improvement over conventional source-optimized quantizer.

关键词： combined source-channel coding turbo codes vector quantization

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Distributed Luby transform coding for three-source single-relay networks based on the deconvolution of robust soliton distribution

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IET COMMUNICATIONS 2015年第2期9卷 167-176页

作者： Shao, Hanqin Xu, Dazhuan Zhang, Xiaofei Nanjing Univ Aeronaut & Astronaut Coll Elect & Informat Engn Nanjing 210016 Peoples R China

The distributed Luby transform (LT) coding is investigated for the multisource networks, especially with three sources. Based on the three-source single-relay network model, the authors propose a threefold deconvolution method of the robust soliton distribution (RSD). The deconvolved distribution is used at each source, and a simple and feasible combining algorithm is developed for re-encoding at the relay. Such a modified LT code with three sources (MLT-3) is constructed. Simulation results verify that the overall degree distribution of the proposed MLT-3 codes agrees well with the RSD. The performance of MLT-3 codes is evaluated and compared with other coding schemes. Simulations reveal that MLT-3 codes have similar behaviour with the two-source or four-source distributed LT codes and the benefits are observed in comparison with the separate LT codes. Simulations also show that MLT-3 codes exhibit good performance on various erasure channels.

关键词： transform coding network coding relay networks (telecommunication) deconvolution solitons combined source-channel coding modifled LT code with three sources erasure channel four-source distributed LT code two-source distributed LT code MLT-3 code RSD multisource network robust soliton distribution deconvolution three-source single-relay network distributed Luby transform coding

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Adaptive source-channel subband video coding for wireless channels

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 1998年第9期16卷 1830-1839页

作者： Srinivasan, M Chellappa, R Univ Maryland Dept Elect Engn College Pk MD 20742 USA Univ Maryland Ctr Automat Res College Pk MD 20742 USA

This paper presents a general framework for combined source-channel coding within the context of subband coding. The unequal importance of subbands in reconstruction of the source is exploited by an appropriate allocation of source and channel coding rates for the coding and transmission of subbands over a noisy channel, For each subband, the source coding rate as well as the level of protection (quantified by the channel coding rate) are jointly chosen to minimize the total end-to-end mean-squared distortion suffered by the source. This allocation of source and channel coding rates is posed as a constrained optimization problem, and solved using a generalized bit allocation algorithm. The optimal choice of source and channel coding rates depends on the state of the physical channel. These results are extended to transmission over fading channels using a finite state model, where every state corresponds to an additive white Gaussian noise (AWGN) channel. A coding strategy is also developed that minimizes the average distortion when the channel state is unavailable at the transmitter. Experimental results are provided that demonstrate application of these combined source-channel coding strategies on video sequences.

关键词： coding for noisy channels combined source-channel coding finite-state channels robust source coding transmission over noisy channels video

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Bit-estimate based decoding for vector quantization over noisy channels with intersymbol interference

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IEEE TRANSACTIONS ON COMMUNICATIONS 2000年第8期48卷 1309-1317页

作者： Skoglund, MO Royal Inst Technol Dept Signals Sensors & Syst SE-10044 Stockholm Sweden

We introduce new techniques for quantization over noisy channels with intersymbol interference. We focus on the decoding problem, and present a decoder structure that allows the decoding to be based on soft minimum mean-square-error estimates of the transmitted bits. The new bit-estimate based decoder provides a structured lower-complexity approximation of optimal decoding for general codebooks, and for so-called linear mapping codebooks, it is shown that its implementation becomes particularly simple, We investigate decoding based on optimal bit-estimates, and on suboptimal estimates of lower computational complexity. We also consider encoder optimization and combined source-channel code design. Numerical simulations demonstrate that bit estimate based de coding is able to outperform a two-stage decision-based approach implemented using Viterbi sequence detection plus table look-up source decoding. The simulations also show that decoding based on suboptimal bit-estimates performs well, at a considerably lowered complexity.

关键词： combined source-channel coding equalization intersymbol interference soft decoding vector quantization

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Transmit diversity technique based on joint slow-time coding with circulating code

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IET RADAR SONAR AND NAVIGATION 2017年第8期11卷 1243-1250页

作者： Li, Shengyuan Zhang, Linrang Liu, Nan Zhang, Juan Tang, Shiyang Xidian Univ Natl Lab Radar Signal Proc Xian 710071 Shaanxi Peoples R China

Circulating code provides a simple way to achieve transmit diversity with stable gain along wide angular coverage, whereas this property is at a cost of degraded range resolution. In this study, a novel transmit diversity technique referred to as joint slow-time coding with circulating code (STCC) is proposed and investigated to solve the above problem. The STCC can be regarded as a coded pulse sequence of circulating code which achieves full bandwidth after synthesising the frequency band of each pulse. It improves the range resolution while maintaining stable gain property of circulating code. At the analysis stage, the transmit ambiguity function (AF) is used to assess the angle-range property of STCC. Based on the transmit AF, a general processing procedure at receive side is derived. Finally, numerical experiments are carried out using simulated data. The performance assessment shows that the proposed technique is superior to circulating code in range resolution and interfering signal suppression.

关键词： combined source-channel coding signal processing range resolution interfering signal suppression angle-range property AF transmit ambiguity function analysis stage frequency band coded pulse sequence STCC joint slow-time coding with circulating code wide angular coverage transmit diversity technique

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A High-Throughput FPGA Architecture for Joint source and channel Decoding

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IEEE ACCESS 2017年 5卷 2921-2944页

作者： Brejza, Matthew F. Maunder, Robert G. Al-Hashimi, Bashir M. Hanzo, Lajos Univ Southampton Dept Elect & Comp Sci Southampton SO17 1BJ Hants England

In the wireless transmission of multimedia information, the achievable transmission throughput and latency may be limited by the processing throughput and latency associated with source and channel coding. Ultra-high throughput and ultra-low latency processing of source and channel coding are required by the emerging new video transmission applications, such as the first-person remote control of unmanned vehicles. The recently proposed unary error correction (UEC) code facilitates the joint source and channel coding (JSCC) of video information at transmission throughputs that approach the capacity of the wireless channel. In this paper, we propose the first hardware implementation of the UEC code that achieves the high processing throughputs as well as ultra-low processing latencies required. This is achieved by extending the application of the recently proposed fully parallel turbo decoder (FPTD) from pure stand-alone channel coding to JSCC. This paper also proposes several novel improvements to the FP ID, in order to increase its hardware efficiency and supported frame length. We demonstrate the application of these improvements to both the long term evolution turbo code and the UEC code. We synthesize the proposed fully parallel design on a mid-range field programmable gate array, achieving a throughput of 450 Mbps, as well as a factor of 2.4 hardware efficiency improvement over previous implementations of the FPTD.

关键词： Turbo codes combined source-channel coding channel coding decoding field programmable gate arrays throughput wireless communication

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Control Over Gaussian channels With and Without source-channel Separation

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IEEE TRANSACTIONS ON AUTOMATIC CONTROL 2019年第9期64卷 3690-3705页

作者： Khina, Anatoly Garding, Elias Riedel Pettersson, Gustav M. Kostina, Victoria Hassibi, Babak CALTECH Dept Elect Engn Pasadena CA 91125 USA Tel Aviv Univ Dept Elect Engn Syst IL-6997801 Tel Aviv Israel Univ Cambridge Dept Appl Math & Theoret Phys Ctr Math Sci Cambridge CB3 0WA England KTH Royal Inst Technol Sch Engn Sci SE-10044 Stockholm Sweden

We consider the problem of controlling an unstable linear plant with Gaussian disturbances over an additive white Gaussian noise channel with an average transmit power constraint, where the signaling rate of communication may be different from the sampling rate of the underlying plant. Such a situation is quite common since sampling is done at a rate that captures the dynamics of the plant and that is often lower than the signaling rate of the communication channel. This rate mismatch offers the opportunity of improving the system performance by using coding over multiple channel uses to convey a single control action. In a traditional, separation-based approach to source and channel coding, the analog message is first quantized down to a few bits and then mapped to a channel codeword whose length is commensurate with the number of channel uses per sampled message. Applying the separation-based approach to control meets its challenges: first, the quantizer needs to be capable of zooming in and out to be able to track unbounded system disturbances, and second, the channel code must be capable of improving its estimates of the past transmissions exponentially with time, a characteristic known as anytime reliability. We implement a separated scheme by leveraging recently developed techniques for control over quantized-feedback channels and for efficient decoding of anytime-reliable codes. We further propose an alternative, namely, to perform analog joint source-channel coding, by this avoiding the digital domain altogether. For the case where the communication signaling rate is twice the sampling rate, we employ analog linear repetition as well as Shannon-Kotel'nikov maps to show a significant improvement in stability margins and linear-quadratic costs over separation-based schemes. We conclude that such analog coding performs better than separation, and can stabilize all moments as well as guarantee almost-sure stability.

关键词： channel coding combined source-channel coding Gaussian channel Lloyd-Max algorithm networked control systems quantization tree codes

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Hadamard-based soft decoding for vector quantization over noisy channels

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IEEE TRANSACTIONS ON INFORMATION THEORY 1999年第2期45卷 515-532页

作者： Skoglund, M Hedelin, P Royal Inst Technol Dept Signal Sensors & Syst Signal Proc Grp S-10044 Stockholm Sweden Chalmers Univ Technol Dept Signals & Syst Informat Theory Grp S-41296 Gothenburg Sweden

We present an estimator-based, or soft, vector quantizer decoder for communication over a noisy channel. The decoder is optimal according to the mean-square error criterion, and Hadamard-based in the sense that a Hadamard transform representation of the vector quantizer is utilized in the implementation of the decoder, An efficient algorithm for optimal decoding is derived. We furthermore investigate suboptimal versions of the decoder, providing good performance at lower complexity. The issue of joint encoder-decoder design is considered both for optimal and suboptimal decoding. Results regarding the channel distortion and the structure of a channel robust code are also provided. Through numerical simulations, soft decoding is demonstrated to outperform hard decoding in several aspects.

关键词： combined source-channel coding estimation index assignment noisy channels soft decoding vector quantization

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