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22
Capacity of Fading Channels with Channel Side Information
, 1997
"... We obtain the Shannon capacity of a fading channel with channel side information at the transmitter and receiver, and at the receiver alone. The optimal power adaptation in the former case is "waterpouring" in time, analogous to waterpouring in frequency for timeinvariant frequencyselective fadi ..."
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Cited by 395 (23 self)
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We obtain the Shannon capacity of a fading channel with channel side information at the transmitter and receiver, and at the receiver alone. The optimal power adaptation in the former case is "waterpouring" in time, analogous to waterpouring in frequency for timeinvariant frequencyselective fading channels. Inverting the channel results in a large capacity penalty in severe fading.
Common Randomness in Information Theory and Cryptography Part II: CR capacity
 IEEE Trans. Inform. Theory
, 1993
"... The CR capacity of a twoteminal model is defined as the maximum rate of common randomness that the terminals can generate using resources specified by the given model. We determine CR capacity for several models, including those whose statistics depend on unknown parameters. The CR capacity is show ..."
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Cited by 152 (12 self)
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The CR capacity of a twoteminal model is defined as the maximum rate of common randomness that the terminals can generate using resources specified by the given model. We determine CR capacity for several models, including those whose statistics depend on unknown parameters. The CR capacity is shown to be achievable robustly, by common randomness of nearly uniform distribution no matter what the unknown parameters are. Our CR capacity results are relevant for the problem of identification capacity, and also yield a new result on the regular (transmission) capacity of arbitrarily varying channels with feedback. Key words: common randomness, identification capacity, correlated sources, arbitrarily varying channel, feedback, randomization. I. Csisz'ar was partially supported by the Hungarian National Foundation for Scientific Research, Grant T16386. 1 Introduction Suppose two terminals, called Terminal X and Terminal Y, have resources such as access to side information and communica...
Reliable Communication Under Channel Uncertainty
 IEEE TRANS. INFORM. THEORY
, 1998
"... In many communication situations, the transmitter and the receiver must be designed without a complete knowledge of the probability law governing the channel over which transmission takes place. Various models for such channels and their corresponding capacities are surveyed. Special emphasis is pla ..."
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Cited by 119 (3 self)
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In many communication situations, the transmitter and the receiver must be designed without a complete knowledge of the probability law governing the channel over which transmission takes place. Various models for such channels and their corresponding capacities are surveyed. Special emphasis is placed on the encoders and decoders which enable reliable communication over these channels.
The Gaussian Watermarking Game
, 2000
"... Watermarking models a copyright protection mechanism where an original source sequence or "covertext" is modified before distribution to the public in order to embed some extra information. The embedding should be transparent (i.e., the modified data sequence or "stegotext" should be similar to the ..."
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Cited by 107 (8 self)
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Watermarking models a copyright protection mechanism where an original source sequence or "covertext" is modified before distribution to the public in order to embed some extra information. The embedding should be transparent (i.e., the modified data sequence or "stegotext" should be similar to the covertext) and robust (i.e., the extra information should be recoverable even if the stegotext is modified further, possibly by a malicious "attacker"). We compute the coding capacity of the watermarking game for a Gaussian covertext and squarederror distortions. Both the public version of the game (covertext known to neither attacker nor decoder) and the private version of the game (covertext unknown to attacker but known to decoder) are treated. While the capacity of the former cannot, of course, exceed the capacity of the latter, we show that the two are, in fact, identical. These capacities depend critically on whether the distortion constraints are required to be met in expectation or with probability one. In the former case the coding capacity is zero, whereas in the latter it coincides with the value of related zerosum dynamic mutual informations games of complete and perfect information. # Parts of this work were presented at the 2000 Conference on Information Sciences and Systems (CISS '00), Princeton University, Princeton, NJ, March 1517, 2000, and at the 2000 IEEE International Symposium on Information Theory (ISIT '00), Sorrento, Italy, June 2530, 2000.
A Framework for Evaluating the DataHiding Capacity of Image Sources
 IEEE Trans. on Image Processing
, 2002
"... An informationtheoretic model for image watermarking and data hiding is presented in this paper. Recent theoretical results are used to characterize the fundamental capacity limits of image watermarking and datahiding systems. Capacity is determined by the statistical model used for the host im ..."
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Cited by 25 (4 self)
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An informationtheoretic model for image watermarking and data hiding is presented in this paper. Recent theoretical results are used to characterize the fundamental capacity limits of image watermarking and datahiding systems. Capacity is determined by the statistical model used for the host image, by the distortion constraints on the data hider and the attacker, and by the information available to the data hider, to the attacker, and to the decoder. We consider autoregressive, blockDCT and wavelet statistical models for images and compute datahiding capacity for compressed and uncompressed hostimage sources. Closedform expressions are obtained under sparsemodel approximations. Models for geometric attacks and distortion measures that are invariant to such attacks are considered.
A Gametheoretic Look at the Gaussian Multiaccess Channel
 DIMACS Workshop on Network Information Theory, Rutgers University, Piscataway
, 2002
"... We study the issue of how to fairly allocate communication rate among the users of a Gaussian multiaccess channel. All users are assumed to value rate equally and each is assumed to have no limit on its desired rate. We adopt a cooperative gametheoretic viewpoint, i.e. it is assumed that the use ..."
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Cited by 22 (0 self)
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We study the issue of how to fairly allocate communication rate among the users of a Gaussian multiaccess channel. All users are assumed to value rate equally and each is assumed to have no limit on its desired rate. We adopt a cooperative gametheoretic viewpoint, i.e. it is assumed that the users can potentially form coalitions off line to threaten other users with jamming the channel, using this as an argument for deserving a larger share of the rate. To determine the characteristic function of the game, we first determine the capacity region of the Gaussian multiaccess arbitrarily varying channel, with an operational meaning of capacity somewhat modified from the usual one, which is more appropriate to our context and permits time sharing. We then propose a solution concept for the game through a set of natural fairness axioms and prove that there exists a unique fair allocation that satisfies the axioms. Moreover, we demonstrate that the unique allocation is always feasible and lies in the core of the game.
The compound channel capacity of a class of finitestate channels
 IEEE Trans. Inform. Theory
, 1998
"... Abstract — A transmitter and receiver need to be designed to guarantee reliable communication on any channel belonging to a given family of finitestate channels defined over common finite input, output, and state alphabets. Both the transmitter and receiver are assumed to be ignorant of the channel ..."
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Cited by 14 (1 self)
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Abstract — A transmitter and receiver need to be designed to guarantee reliable communication on any channel belonging to a given family of finitestate channels defined over common finite input, output, and state alphabets. Both the transmitter and receiver are assumed to be ignorant of the channel over which transmission is carried out and also ignorant of its initial state. For this scenario we derive an expression for the highest achievable rate. As a special case we derive the compound channel capacity of a class of Gilbert–Elliott channels. Index Terms—Compound channel, error exponents, finitestate channels, Gilbert–Elliott channel, universal decoding. I.
Analysis of an onoff jamming situation as a dynamic game
 IEEE Trans. Commun
, 2000
"... Abstract—The process of communication jamming can be modeled as a twoperson zerosum noncooperative dynamic game played between a communicator (a transmitterreceiver pair) and a jammer. We consider a oneway timeslotted packet radio communication link in the presence of a jammer, where the data r ..."
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Cited by 13 (0 self)
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Abstract—The process of communication jamming can be modeled as a twoperson zerosum noncooperative dynamic game played between a communicator (a transmitterreceiver pair) and a jammer. We consider a oneway timeslotted packet radio communication link in the presence of a jammer, where the data rate is fixed and 1) in each slot, the communicator and jammer choose their respective power levels in a random fashion from a zero and a positive value; 2) both players are subject to temporal energy constraints which account for protection of the communicating and jamming transmitters from overheating. The payoff function is the time average of the mean payoff per slot. The game is solved for certain ranges of the players ' transmitter parameters. Structures of steadystate solutions to the game are also investigated. The general behavior of the players ' strategies and payoff increment is found to depend on a parameter related to the payoff matrix, which we call the payoff parameter, and the transmitters ' parameters. When the payoff parameter is lower than a threshold, the optimal steadystate strategies are mixed and the payoff increment constant over time, whereas when it is greater than the threshold, the strategies are pure, and the payoff increment exhibits oscillatory behavior. Index Terms—Communication jamming, grid solution, noncooperative dynamic game, optimal strategies, temporal energy constraints. I.
Robust Decoding for Timing Channels
 IEEE. Trans. Inform. Theory
, 2000
"... Abstract—To transmit information by timing arrivals to a singleserver queue, we consider using the exponential server channel’s maximumlikelihood decoder. For any server with service times that are stationary and ergodic with mean 1 seconds, we show that the rate 1 nats per second (capacity of the ..."
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Cited by 10 (2 self)
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Abstract—To transmit information by timing arrivals to a singleserver queue, we consider using the exponential server channel’s maximumlikelihood decoder. For any server with service times that are stationary and ergodic with mean 1 seconds, we show that the rate 1 nats per second (capacity of the exponential server timing channel) is achievable using this decoder. We show that a similar result holds for the timing channel with feedback. We also show that if the server jams communication by adding an arbitrary amount of time to the nominal service time, then the rate 1 1 2 ( 1 + 2) nats per second is achievable with random codes, where the nominal service times are stationary and ergodic with mean 1 1 seconds, and the arithmetic mean of the delays added by the server does not exceed 1 2 seconds. This is a model of an arbitrarily varying channel where the current delay and the current input can affect future outputs. We also show the counterpart of these results for singleserver discretetime queues. Index Terms—Arbitrarily varying channel, channels with feedback, mismatched decoder, pointprocess channel, robust decoding, singleserver queue, timing channels. I.
Watermarking and Digital Signature Techniques for Multimedia Authentication and Copyright Protection
, 2000
"... Multimedia authentication techniques are required in order to ensure trustworthiness of multimedia data. They are usually designed based on two kinds of tools: digital signature or watermarking. Digital signature is a nonrepudiatible, encrypted version of the message digest extracted from the data. ..."
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Cited by 10 (2 self)
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Multimedia authentication techniques are required in order to ensure trustworthiness of multimedia data. They are usually designed based on two kinds of tools: digital signature or watermarking. Digital signature is a nonrepudiatible, encrypted version of the message digest extracted from the data. Watermarking techniques consider multimedia data as a communication channel transmitting owner identification or content integrity information. Given an objective for multimedia authentication to reject the cropandreplacement process and accept contentpreserving manipulations, traditional digital signature or watermarking methods cannot be directly applied. In this thesis, we first propose robust digital signature methods that have proved to be useful for such types of content authentication. Also, we have developed a novel semifragile watermarking technique to embed the proposed robust digital signatures. We have implemented a unique SelfAuthenticationandRecovery Images (SARI) system, which can accept quantizationbased lossy compression to a determined degree without any false alarms and can sensitively detect and locate malicious manipulations. Furthermore, the corrupted areas can be approximately recovered by the information hidden in the other part of the content. The amount of information embedded in our SARI system has nearly reached the theoretical maximum zeroerror information hiding capacity of digital images. Watermarking is a promising solution that can protect the copyright of multimedia data through transcoding. A reasonable expectation of applying watermarking techniques for copyright protection is to consider specific application scenarios, because the distortion behavior involved in these cases (geometric distortion and pixel value distortion) could be reasonably predictable. We propose a practical public watermarking algorithm that is robust to rotation, scaling, and/or translation (RST) distortion. This proposed algorithm plays an important role in our design of the public watermarking technique which survives the image printandscan process. In addition, we present our original work in analyzing the theoretical watermarking capacity bounds for digital images, based on the information theory and the characteristics of the human vision system. We investigate watermarking capacity in three directions: the zeroerror capacity for public watermarking in magnitudebounded noisy environments, the watermarking capacity based on domainspecific masking effects, and the watermarking capacity issues based on sophisticated Human Vision System models.