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This study investigates multi-layer coding over a dirty-paper channel. First, it is demonstrated that superposition coding in such channel still achieves the capacity of interference-free additive white Gaussian noise channel when the transmitter is non-causally aware of interference signal. Then, the problem is extended to the dirty-paper block fading channel, where it is shown that in the lack of channel information at the transmitter, the so-called broadcast approach maximises the average achievable rate of such channel.

In this paper, we study the state-dependent Gaussian wiretap channel with action encoder and noncausal state at the transmitter, which is also called the action-dependent dirty paper wiretap channel. Two lower bounds on the secrecy capacity of this model are provided, and we find that the two bounds have their advantages and disadvantages, i.e., none of the two always performs better than the other. In addition, we find that taking action on the state helps to increase the achievable secrecy rate of the dirty paper wiretap channel.

The dirty paper wiretap channel, also referred to as the Gaussian wiretap channel with noncausal state at the transmitter, is revisited. First, we determine the secrecy capacity of the dirty paper wiretap channel with noiseless feedback, where the feedback channel is from the legitimate receiver to the transmitter. Next, we obtain lower and upper bounds on the secrecy capacity of the action-dependent dirty paper wiretap channel with noiseless feedback, and show that these bounds meet for a special case. Unlike the fact that action on the state helps to enhance the capacity of the dirty paper channel with feedback, numerical results of this paper indicate that it may not help to enhance the secrecy capacity of the dirty paper wiretap channel with feedback.

The problem of joint information transmission and input signalling estimation over a state-dependent channel is considered. The general single-letter upper and lower bounds of the optimal capacity-distortion trade-offs are provided. For the Gaussian dirty paper channel, we calculate the bounds by choosing parameters carefully, and obtain a computable form eventually. In such a way, we obtain a complete characterization for this problem setting.

The dirty paper wiretap channel, also referred to as the Gaussian wiretap channel with noncausal channel state at the transmitter, plays an important role in wireless physical layer security. In this paper, the dirty paper wiretap channel is revisited by considering actions on the channel state, i.e., the transmitter generates an action sequence that affects the formation of the channel state. Lower and upper bounds on the secrecy capacity of this model are proposed, and numerical results indicate that the actions on the state help to increase the achievable secrecy rate of the dirty paper wiretap channel. The study of this paper offers a new option for enhancing the secrecy rates of the state-dependent wiretap channel models.

The Oblivious Relay serves users without a need to know the users error correcting codes. We extend the oblivious relay concept to channels with interference which is known to the transmitter but not to the receiver. Our system uses structured modulation and coding based on lattices. We show that when the interference is known non-causally, it's influence can be overcome wholly and that in simpler causal schemes the performance is usually within the shaping loss of 0.254 bits/channel use from the optimal performance attainable with large lattices.

In this paper, we study the achievable region for a Gaussian broadcast channel in the presence of an additional interference at the receivers. We consider that a noisy version of this interference is known to the transmitter and the receivers. A nested lattice code coupled with a dirty paper code is used to compute the achievable region. A two phase causal encoding technique is also proposed in which the interference signal is estimated at the end of the first phase and then the desired signal is transmitted in the second phase. Numerical results show that causal knowledge of the interference can significantly improve the achievable rate region over a scheme that does not use interference cancellation. Results are also shown when the transmitter operates in both half-duplex and fullduplex modes. Index Terms—

A modified version of Costa's dirty paper channel is studied, in which both the input signal and the state experience stationary and ergodic time-varying fading. The fading coefficients are assumed to be known exclusively at the receiver. An inner bound of the achievable rates using lattice codes is derived and compared to an outer bound of the capacity. For a wide range of fading distributions, the gap to capacity is within a constant value that does not depend on either the power of the input signal or the state. The results presented in this paper are applied to a class of ergodic fading broadcast channels with receive channel state information, where the achievable rate region is shown to be close to capacity under certain configurations.

In this paper, the problem of writing on a dirty paper in the presence of jamming is examined. We consider an AWGN channel with an additive white Gaussian state and an additive adversarial jammer. The state is assumed to be known non-causally to the encoder and the jammer but not to the decoder. The capacity of the channel in the presence of a jammer is determined. A surprising result that this capacity is equal to the capacity of a relaxed version of the problem, where the state is also known non-causally to the decoder, is proved.

Dirty paper codes are a powerful tool for combating known interference. However, there is a significant difference between knowing the transmitted interference sequence and knowing the received interference sequence, especially when the channel modifying the interference is uncertain. We present an upper bound on the capacity of a compound vector dirty paper channel where although an additive Gaussian sequence is known to the transmitter, the channel matrix between the interferer and receiver is uncertain but known to lie within a bounded set. Our bound is tighter than previous bounds in the low-SIR regime for the scalar version of the compound dirty paper channel and employs a construction that focuses on the relationship between the dimension of the message-bearing signal and the dimension of the additive state sequence. Additionally, a bound on the high-SNR behavior of the system is established., Comment: to be presented at ISIT 2013

Witsenhausen's counterexample was proposed more than four decades ago in order to show that affine control strategies are not optimal for systems with non-classical information patterns. Finding the optimal solution to Witsenhausen's problem however remains an open problem. Recently, the stochastic control community has re-discovered Costa's Dirty Paper result as a potential solution to Witsenhausen's problem. In this paper the similarities and differences between Witsenhausen's scenario and multimedia security problems are reviewed, and the historical evolution of the solutions to Witsenhausen's problem compared with those proposed for watermarking detection.

Recently there has been a lot of success in using the deterministic approach to provide approximate characterization of Gaussian network capacity. In this paper, we take a deterministic view and revisit the problem of wiretap channel with side information. A precise characterization of the secrecy capacity is obtained for a linear deterministic model, which naturally suggests a coding scheme which we show to achieve the secrecy capacity of the degraded Gaussian model (dubbed as "secret writing on dirty paper") to within half a bit., Removed the section on writing on fading paper; improved the gap result from $(1/2)\log3$ bits to half a bit; added a section on secret-key agreement via dirty-paper coding; revised version submitted to the IEEE Transaction on Information Theory

A bound on the capacity of the causal dirty paper problem with arbitrary interference and general independent identically distributed additive noise is derived. In particular, it is shown that for the case of Gaussian noise the capacity is upper bounded by log 2 (1 + SNR over e) bits per real dimension. This bound is useful for SNR ≤ e(e - 2).

Existing dirty-paper coding (DPC) schemes based on binned FEC codes lack of tractable BER analysis, hence it is difficult to predict the performance behavior of DPC. In this paper, we derive closed-form BER upper bounds of binned Walsh-Hadamard codes and binned Gold codes as DPC. Their BER upper bounds are verified to be very tight under the condition that the channel contains side information only, or side information plus noise.

International audience; Benchmarking watermarking systems now goes beyond only evaluating the ability of the embedded watermark to with- stand common signal primitives such as filtering, resampling, lossy compression, D/A-A/D conversions, etc. Evaluation procedures have to consider how much information leaks from a watermarking system since such knowledge could prove most helpful to design very powerful attacks. This paper further refines an attack on dirty paper watermarking schemes which relies on security weaknesses i.e. information leakage. In particular, additional constraints are introduced to be able to handle ‘complex' trellises. Moreover, the ef- ficiency of this attack has been evaluated for different trel- lis configurations. Quite counter-intuitively, increasing the number of states in the trellis seems to enhance both the robustness and the security of the system.

International audience; This paper analyses the security of dirty paper trellis (DPT) watermarking schemes which use both informed coding and informed em- bedding. After recalling the principles of message embedding with DPT watermarking, the secret parameters of the scheme are highlighted. The security weaknesses of DPT watermarking are then presented: in the wa- termarked contents only attack (WOA) setup, the watermarked data-set exhibits clusters corresponding to the different patterns attached to the arcs of the trellis. The K-means clustering algorithm is used to estimate these patterns and a co-occurrence analysis is performed to retrieve the connectivity of the trellis. Experimental results demonstrate that it is possible to accurately estimate the trellis configuration, which enables to perform attacks much more efficient than simple additive white Gaus- sian noise (AWGN).

In this paper we want to make a fair comparison between TDMA and DPC in terms of the BER region and maximum number of satisfied users. For this purpose we choose the coding/decoding schemes as follows : DPC is based on a trellis coded quantization implementation and successive coding while TDMA uses trellis coded modulation. Simulation results are provided both for the perfect and imperfect channel state information cases. In the perfect CSI case all the tested scenarios show that TDMA generally outperfoms DPC. In the imperfect CSI case DPC is shown to be less sensitive than TDMA to channel estimation errors.

Dirty paper coding are relevant for wireless networks, multiuser channels, and digital watermarking. We show that the problem of dirty paper is essentially equivalent to some classes of constrained memories, and we explore the binary so-called nested codes, which are used for efficient coding and error-correction on such channels and memories. © Springer-Verlag Berlin Heidelberg 2006.

Structured codes are known to be necessary in practical implementations of capacity-approaching "dirty paper schemes". In this paper we study the performance of a recently proposed dirty paper technique, by Erez and ten Brink which, to the authors' knowledge, is firstly applied to data-hiding, and compare it with other existing approaches. Specifically, we compare it with conventional side-informed schemes previously used in data-hiding based on repetition and turbo coding. We show that a significant improvement can be achieved using Erez and ten Brink's proposal. We also study the considerations we have to take into account when these codes are used in data-hiding, mainly related with perceptual questions.

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

We present practical codes designed for the Gaussian dirty paper channel. We show that the dirty paper decoding problem can be transformed into an equivalent multiple-access problem, for which we apply superposition coding. Our approach is a generalization of the nested lattices approach of Zamir et al. (2002). We present simulation results which confirm the effectiveness of our methods.

The many recent publications that focus upon watermarking with side information at the embedder emphasize the fact that this side information can be used to improve practical capacity. Many of the proposed algorithms use quantization to carry out the embedding process. Although both powerful and simple, recovering the original quantization levels, and hence the embedded data, can be difficult if the image amplitude is modified. In our paper, we present a method that is similar to the existing class of quantization-based techniques, but is different in the sense that we first apply a projection to the image data that is invariant to a class of amplitude modifications that can be described as order preserving. Watermark reading and embedding is done with respect to the projected data rather than the original. Not surprisingly, by requiring invariance to amplitude modifications we increase our vulnerability to other types of distortions. Uniform quantization of the projected data generally leads to non-uniform quantization of the original data, which in turn can cause greater susceptibility to additive noise. Later in the paper we describe a strategy that results in an effective compromise between invariance to amplitude modification and noise susceptibility.

An undesirable side effect of many watermarking and data-hiding schemes is that the host signal into which auxiliary data is embedded is distorted. Finding an optimal balance between the amount of information embedded and the induced distortion is therefore an active field of research. In recent years, with the rediscovery of Costa's seminal paper Writing on Dirty Paper , there has been considerable progress in understanding the fundamental limits of the capacity versus distortion of watermarking and data-hiding schemes. For some applications, however, no distortion resulting from auxiliary data, however small, is allowed. In these cases the use of reversible data-hiding methods provide a way out. A reversible data-hiding scheme is defined as a scheme that allows complete and blind restoration (i.e. without additional signaling) of the original host data. Practical reversible data-hiding schemes have been proposed by Fridrich et al., but little attention has been paid to the theoretical limits. Some first results on the capacity of reversible watermarking schemes have been derived. The reversible schemes considered in most previous papers have a highly fragile nature: in those schemes, changing a single bit in the watermarked data would prohibit recovery of both the original host signal as well as the embedded auxiliary data. It is the purpose of this paper to repair this situation and to provide some first results on the limits of robust reversible data-hiding. Admittedly, the examples provided in this paper are toy examples, but they are indicative of more practical schemes that will be presented in subsequent papers.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.