This paper examines near-capacity dirty-paper code designs based on source–channel coding. We first point out that the performance loss in signal-to-noise ratio (SNR) in our code designs can be broken into the sum of the packing loss from channel coding and a modulo loss, which is a function of the granular loss from source coding and the target dirty-paper coding rate (or SNR). We then examine practical designs by combining trellis-coded quantization (TCQ) with both systematic and nonsystematic irregular repeat–accumulate (IRA) codes. Like previous approaches, we exploit the extrinsic information transfer (EXIT) chart technique for capacity-approaching IRA code design; but unlike previous approaches, we emphasize the role of strong source coding to achieve as much granular gain as possible using TCQ. Instead of systematic doping, we employ two relatively shifted TCQ codebooks, where the shift is optimized (via tuning the EXIT charts) to facilitate the IRA code design. Our designs synergistically combine TCQ with IRA codes so that they work together as well as they do individually. By bringing together TCQ (the best quantizer from the source coding community) and EXIT chart-based IRA code designs (the best from the channel coding community), we are able to approach the theoretical limit of dirty-paper coding. For example, at 0.25 bit per symbol (b/s), our best code design (with 2048-state TCQ) performs only 0.630 dB away from the Shannon capacity.

Driven by applications in data-hiding, MIMO broadcast channel coding, precoding for interference cancellation, and transmitter cooperation in wireless networks, Costa coding has lately become a very active research area. In this paper, we first offer code design guidelines in terms of source- channel coding for algebraic binning. We then address practical code design based on nested lattice codes and propose nested turbo codes using turbo-like trellis-coded quantization (TCQ) for source coding and turbo trellis-coded modulation (TTCM) for channel coding. Compared to TCQ, turbo-like TCQ offers structural similarity between the source and channel coding components, leading to more efficient nesting with TTCM and better source coding performance. Due to the difference in effective dimensionality between turbo-like TCQ and TTCM, there is a performance tradeoff between these two components when they are nested together, meaning that the performance of turbo-like TCQ worsens as the TTCM code becomes stronger and vice versa. Optimization of this performance tradeoff leads to our code design that outperforms existing TCQ/TCM and TCQ/TTCM constructions and exhibits a gap of 0.94, 1.42 and 2.65 dB to the Costa capacity at 2.0, 1.0, and 0.5 bits/sample, respectively.

Driven by the applications in data hiding, multiple-input multiple-output broadcast channel coding, precoding for interference cancellation, and transmitter cooperation in wireless networks, Costa coding has lately become a very active research area. In this paper, we first offer code design guidelines in terms of source channel coding for algebraic binning. We then address a practical code design based on nested lattice codes, and propose nested turbo codes by using turbo-like trellis-coded quantization (TCQ) for source coding and turbo trellis-coded modulation (TTCM) for channel coding. Compared to the TCQ, the turbo-like TCQ offers a structural similarity between the source and channel coding components, leading to a more efficient nesting with TTCM and a better source coding performance. Due to the difference in effective dimensionality between turbo-like TCQ and TTCM, there is a performance tradeoff between these two components when they are nested together, meaning that the performance of the turbo-like TCQ worsens as the TTCM code becomes stronger and vice versa. The optimization of this performance tradeoff leads to our code design that outperforms existing TCQ/TCM and TCQ/TTCM constructions, and exhibits a gap of 0.94, 1.42, and 2.65 dB to the Costa capacity at 2.0, 1.0, and 0.5 b/s, respectively.

Nested lattice quantization provides a practical scheme for Wyner-Ziv coding. This paper examines the high-rate performance of nested lattice quantizers and gives the theoretical performance for general continuous sources. In the quadratic Gaussian case, as the rate increases, we observe an increasing gap between the performance of finite-dimensional nested lattice quantizers and the Wyner-Ziv distortion-rate function. We argue that this is because the boundary gain decreases as the rate of the nested lattice quantizers increases. To increase the boundary gain and ultimately boost the overall performance, a new practical Wyner-Ziv coding scheme called Slepian-Wolf coded nested lattice quantization (SWC-NQ) is proposed, where Slepian-Wolf coding is applied to the quantization indices of the source for the purpose of compression with side information at the decoder. Theoretical analysis shows that for the quadratic Gaussian case and at high rate, SWC-NQ performs the same as conventional entropy-coded lattice quantization with the side information available at both the encoder and the decoder. Furthermore, a nonlinear minimum mean-square error (MSE) estimator is introduced at the decoder, which is theoretically proven to degenerate to the linear minimum MSE estimator at high rate and experimentally shown to outperform the linear estimator at low rate. Practical designs of one- and two-dimensional nested lattice quantizers together with multilevel low-density parity-check (LDPC) codes for Slepian-Wolf coding give performance close to the theoretical limits of SWC-NQ

A Slepian-Wolf coding scheme for compressing two uniform memoryless binary sources using a single channel code that can achieve arbitrary rate allocation among encoders was outlined in the work of Pradhan and Ramchandran. Inspired by this work, we address the problem of practical code design for general multiterminal lossless networks where multiple memoryless correlated binary sources are separately compressed and sent; each decoder receives a set of compressed sources and attempts to jointly reconstruct them. First, we propose a near-lossless practical code design for the Slepian-Wolf system with multiple sources. For two uniform sources, if the code approaches the capacity of the channel that models the correlation between the sources, then the system will approach the theoretical limit. Thus, the great advantage of this design method is its possibility to approach the theoretical limits with a single channel code for any rate allocation among the encoders. Based on Slepian-Wolf code constructions, we continue with providing practical designs for the general lossless multiterminal network which consists of an arbitrary number of encoders and decoders. Using irregular repeat-accumulate and turbo codes in our designs, we obtain the best results reported so far and almost reach the theoretical bounds.

Based on recent works on source-channel coding for Wyner-Ziv coding, we consider the case with noisy channel in Wyner-Ziv coding and address distributed joint source-channel coding, while targeting at the important application of video transmission over packet erasure channels. The idea is to use a single channel code for both Slepian-Wolf coding (or source coding with side information at the decoder) and erasure protection. We choose Raptor codes - the best approximation to a digital fountain - for the targeted application and study both encoder and decoder designs under the new setting of distributed joint source-channel coding. Our work represents the first in capitalizing the latest in distributed source coding (e.g., Wyner-Ziv video coding) and near-capacity channel coding (e.g., fountain codes) for robust video transmission over erasure channels.

This paper addresses near-capacity dirty-paper code designs based on TCQ and IRA codes, where the former is employed as the most efficient means of vector quantization and the latter for their capacity-approaching performance. By bringing together TCQ - the best quantizer from the source coding community and EXIT chart based IRA code designs - the best from the channel coding community, we are able to approach the theoretical limit of dirty-paper coding. For example, at 0.25 b/s, one of our code designs (with 1024-state TCQ) performs 0.83 dB away from the capacity

This paper presents a Slepian-Wolf coding of n correlated m-ary sources for LDPC codes. On applying the syndrome concept, multilevel codes with low-density parity-check (LDPC) codes can be used to approach the Slepian-Wolf limit at each level. The advantage of LDPC codes is that they can be designed for different correlation models between source outputs and the side information and approach the Slepian-Wolf limits. Specifically, for Slepian-Wolf coding of three sources, a design rule of rates for coding each source, which facilitates code design and allows multistage decoding was proposed.

This paper examines the high-rate performance of low-dimensional nested lattice quantizers for the quadratic Gaussian Wyner-Ziv problem, using a pair of nested lattices with the same dimensionality. As the rate increases, the gap increases between the performances of low dimensional nested lattice quantizers and the Wyner-Ziv rate-distortion function. This gap is due to the relatively weak channel coding component (or coarse lattice) in the nested lattice pair. To enhance the lattice channel code and boost the overall performance, Slepian-Wolf coding is applied to the quantization indices to achieve further compression. Thereby a Wyner-Ziv coding paradigm is introduced using Slepian-Wolf coded nested lattice quantization (SWC-NQ). Theoretical analysis and simulation results show that, for the quadratic Gaussian source and at high rate, SWC-NQ performs the same as traditional entropy-constrained lattice quantization with side information available at both the encoder and decoder.

A Slepian-Wolf coding scheme that can achieve arbitrary rate allocation among two encoders was outlined in the work of Pradhan and Ramchandran. Inspired by this work, we start with a detailed solution for general (asymmetric or symmetric) Slepian-Wolf coding based on partitioning a single systematic channel code, and continue with practical code designs using advanced channel codes. By using systematic IRA and turbo codes, we devise a powerful scheme that is capable of approaching any point on the Slepian-Wolf bound. We further study an extension of the technique to multiple sources, and show that for a particular correlation model among the sources, a single practical channel code can be designed for coding all the sources in symmetric and asymmetric scenarios. If the code approaches the capacity of the channel that models the correlation between the sources, then the system will approach the Slepian-Wolf limit. Using systematic IRA and punctured turbo codes for coding two binary sources, each being independent identically distributed, with correlation modeled by a binary symmetric channel, we obtain results which are 0.04 bits away from the theoretical limit in both symmetric and asymmetric Slepian-Wolf settings.

This paper considers a general multiterminal (MT) system, which consists of L encoders and P decoders. Let X/sub 1/,..., X/sub L/ be memoryless, uniform, correlated random binary vectors of length n, and let x/sub 1/,..., x/sub L/ denote their realizations. Let further /spl Sigma/ = {1,...,L}. The i-th encoder compresses X/sub i/ independently from other encoders. The j-th decoder receives the bitstreams from a set of encoders /spl Sigma//sub j//spl sube/ /spl Sigma/ and jointly decodes them. It should reconstruct the received source messages with arbitrarily small probability of error. To construct a practical coding scheme for this network, we exploit the fact that such a network can be split into P subnetworks, each being regarded as a Slepian-Wolf (SW) coding system with multiple sources. This SW subnetwork consists of a decoder which receives encodings of all X/sub k/'s such that k/spl isin//spl Sigma//sub sw//spl sube//spl Sigma/ and attempts to reconstruct them perfectly. Based on (V. Stankovic et al. 2004), we first provide a code design for this setting, and then extend it to the general case.

This paper addresses practical code design problems for multiterminal communication networks. The basic element of a multiterminal network code is the binning scheme. We aim to develop a unified practical code design paradigm for related problems in multiterminal networks based on source-channel coding for algebraic binning. First, a framework based on Slepian-Wolf coded quantization is highlighted for Wyner-Ziv coding and multiterminal source coding (e.g., the CEO problem). Then, a nested turbo scheme is proposed for Costa coding by exploiting the duality between Costa coding and Wyner-Ziv coding.

It is shown how conventional parallel (turbo) and serial concatenated convolutional codes can be used to compress close to the Slepian-Wolf limit for the correlated binary sources. Conventional refers to codes already used in channel coding. Focusing on the asymmetric case of compression of an equipolarable memoryless binary source with side information at the decoder, the approach is based on modeling the correlation as a channel and using syndromes. The encoding and decoding procedures are explained in detail. The performance achieved is seen to be better than the recently published results using nonconventional turbo codes and close to the Slepian-Wolf limit.

We study the effects of quantization at the output of a binary-input additive white Gaussian noise (BIAWGN) channel on the performance of low-density parity-check (LDPC) codes. The LDPC decoder works with unlimited precision. The quantizer design is based on either optimizing the equivalent channel capacity, cutoff-rate, mean-squared error (MSE) or the LDPC code convergence. All the approaches are compared in search of the most appropriate design criterion.

We show how concatenated (convolutional) codes can be used to compress close to the Wyner-Ziv limit for binary sources. Focusing on the case of lossy compression of an equiprobable memoryless binary source with side information at the decoder, the approach is based on nested binary linear codes, which is the extension of Wyner's lossless compression scheme to the lossy case proposed by Shamai, Verdu and Zamir. Based on our previous work on lossless compression with concatenated codes, we are able to combine the only two previously suggested nested schemes into a novel turbo scheme with improved performance. Our scheme can come within 0.09 bits from the theoretical limit, which to our knowledge is the first result ever reported for the binary Wyner-Ziv problem.

Faster-than-Nyquist signaling introduces intersymbol interference, but increases the bit rate while preserving the signaling bandwidth. For sinc pulses, it has been established that with a small increase in the signaling rate beyond the Nyquist rate, there is no reduction in the minimum Euclidean distance for binary signaling. We generalize these observations to the family of raised-cosine pulses. The structure of the error events that reduce the minimum distance is examined, and constrained coding ideas are suggested that theoretically allow even faster signaling. Then we propose ways of achieving these gains practically by designing appropriate constrained codes and through equalization and iterative joint equalization and decoding (turbo equalization).

It is shown how low-density parity-check (LDPC) codes can be used as an application of the Slepian-Wolf (1973) theorem for correlated binary sources. We focus on the asymmetric case of compression with side information. The approach is based on viewing the correlation as a channel and applying the syndrome concept. The encoding and decoding procedures, i.e. the compression and decompression, are explained in detail. The simulated performance results are better than most of the existing turbo code results available in the literature and very close to the Slepian-Wolf limit.

According to the Slepian-Wolf theorem [1], the output of two correlated sources can be compressed to the same extent without loss, no matter if they communicate with each other or not, provided that the decompression takes place at a common decoder having both compressed outputs available. In this paper, as an application of the Slepian-Wolf theorem, an advanced distributed source coding scheme for correlated images is presented. Assuming that the correlated image is a noisy version of the original, the scheme involves modulo encoding of the pixel values and encoding (compression) of the resulting symbols with binary and nonbinary turbo-codes, so that rate savings are achieved practically without loss.

During the last few years, the mobile wireless industry has been spending considerable effort to enhance the technical characteristics of existing second generation systems in the goal of upgrading their service provision capabilities and of promoting effective integration with data transport networks (the GSM GPRS is an obvious paradigm). This line of action can be anticipated as a first step in the migration path towards 3G systems and has been adopted for two basic reasons: the first is that market demand for wireless data services is currently a small portion of the overall wireless service demand and the second is that the deployment of new technologies in large scale requires gross economical investments. This paper proposes a protocol architecture, a physical configuration and a set of functions for DECT cell clusters that provide access to ISDN transport networks. It also proposes a scheme for the incorporation of these clusters in the numbering and mobility support schemes of existing GSM networks.

The widespread interest for wireless LAN applications has boosted relative research efforts during the last few years. Although both the IEEE and ETSI have proposed wireless LAN standards which utilise the advances in wireless technology to provide high bandwidth, the investigation of the capabilities of applied wireless technologies to provide LAN services are of both technical and economic interest. This paper proposes an implementation oriented architecture and set of functions for a wireless LAN which is based on the ETSI Digital Enhanced Cordless Telecommunications (DECT) protocol. It particularly presents a dynamic bandwidth management scheme, enabling the wireless LAN to efficiently support asynchronous data transfer services characterised by burst mode traffic. For the evaluation of the bandwidth management scheme, the paper proposes an analytic traffic model with adaptive service rate for each system queue and solves it based on a number of logical assumptions. The model is utilised to calculate parameters such as the average delay and the average number of packets in the system queues in order to approximately "describe" the behaviour of the system.

The deployment of DECT based mobile access systems urges for the development of interworking procedures between DECT and existing fixed networks. The B-ISDN infrastructure with its advanced signalling capabilities is an excellent choice to be used as a DECT local network. This paper proposes a reference configuration and an interworking specification for a hybrid DECT- B-ISDN mobile access system. It outlines a B-ISDN mobility control architecture capable of supporting full scale DECT mobility throughout the system and discusses in detail the B-ISDN user and control plane functionality which is necessary for the support of DECT mobility procedures over B-ISDN. The architecture and functionality described herein are implementation oriented and are aimed to support step by step integration of DECT mobile access systems in a core B-ISDN infrastructure.

One of the technological concepts with significant contribution to the evolution of digital telecommunications in the last decades is the ISDN concept. ISDN protocols serve as the main basis for the development of new techniques and technologies for the implementation of complex, advanced digital based services over the existing telecommunications infrastructure. This paper proposes a generic ISDN based platform capable of supporting state of the art BRI and PRI applications incorporating all the latest network management and inter-working developments in the field.

Data traffic originating at mobile infrastructures, such as utilised by DECT mobiles, is, in principle, constant bit rate traffic (CBR). On the other hand, the flexibility of the B-ISDN network to transport data at constant, variable (variable bit rate) or available (available bit rate) bit rates makes it ideal to be utilised as the communication medium among distributed mobile terminals residing at distant wireless networks. This paper proposes an architecture and a set of procedures suitable for use in UMTS-ATM specific platform realisations. The deployed architecture is also enhanced to support all AAL1 functions required for every possible envisaged type of mobile data transport service. It also takes into account all mobile data management requirements necessary for maintaining timing, buffering and delay variations requirements.