Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282949
Zhe Wang, Xiaodong Wang, V. Aggarwal
We consider an energy harvesting network with multiple transmission links in a frequency-selective fading channel. We formulate the problem of joint energy and subchannel allocation for all transmitters over a scheduling period, as a mixed integer program. With the predictions of the harvested energy and subchannel gains, we propose an algorithm to efficiently obtain the energy-subchannel allocations for all links over the scheduling period based on controlled water-filling. The proposed algorithm is shown to be asymptotically optimal when the bandwidth of the subchannel goes to zero. Simulation results demonstrate that the performance of the proposed algorithm is close to the upper-bound on the optimal performance, which is also outperforms various heuristic allocation policies.
{"title":"Energy-subchannel allocation for energy harvesting nodes in frequency-selective channels","authors":"Zhe Wang, Xiaodong Wang, V. Aggarwal","doi":"10.1109/ISIT.2015.7282949","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282949","url":null,"abstract":"We consider an energy harvesting network with multiple transmission links in a frequency-selective fading channel. We formulate the problem of joint energy and subchannel allocation for all transmitters over a scheduling period, as a mixed integer program. With the predictions of the harvested energy and subchannel gains, we propose an algorithm to efficiently obtain the energy-subchannel allocations for all links over the scheduling period based on controlled water-filling. The proposed algorithm is shown to be asymptotically optimal when the bandwidth of the subchannel goes to zero. Simulation results demonstrate that the performance of the proposed algorithm is close to the upper-bound on the optimal performance, which is also outperforms various heuristic allocation policies.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127015290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282439
S. Haddad, O. Lévêque
The present paper focuses on the problem of broadcasting information in the most efficient manner in a large two-dimensional ad hoc wireless network at low SNR and under line-of-sight propagation. A new communication scheme is proposed, where source nodes first broadcast their data to the entire network, despite the lack of sufficient available power. The signal's power is then reinforced via successive back-and-forth beamforming transmissions between different groups of nodes in the network, so that all nodes are able to decode the transmitted information at the end. This scheme is shown to achieve asymptotically the broadcast capacity of the network, which is expressed in terms of the largest singular value of the matrix of fading coefficients between the nodes in the network. A detailed mathematical analysis is then presented to evaluate the asymptotic behavior of this largest singular value.
{"title":"On the broadcast capacity of large wireless networks at low SNR","authors":"S. Haddad, O. Lévêque","doi":"10.1109/ISIT.2015.7282439","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282439","url":null,"abstract":"The present paper focuses on the problem of broadcasting information in the most efficient manner in a large two-dimensional ad hoc wireless network at low SNR and under line-of-sight propagation. A new communication scheme is proposed, where source nodes first broadcast their data to the entire network, despite the lack of sufficient available power. The signal's power is then reinforced via successive back-and-forth beamforming transmissions between different groups of nodes in the network, so that all nodes are able to decode the transmitted information at the end. This scheme is shown to achieve asymptotically the broadcast capacity of the network, which is expressed in terms of the largest singular value of the matrix of fading coefficients between the nodes in the network. A detailed mathematical analysis is then presented to evaluate the asymptotic behavior of this largest singular value.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129226064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282800
R. Schaefer, A. Khisti, H. Poor
The broadcast channel with independent secret keys is studied. In this scenario, a common message has to be securely broadcast to two legitimate receivers in the presence of an eavesdropper. The transmitter shares with each legitimate receiver an independent secret key of arbitrary rate. These keys can either be used as one-time pads to encrypt the common message or can be interpreted as fictitious messages used as randomization resources for wiretap coding. Both approaches are discussed and the secrecy capacity is derived for various cases. Depending on the qualities of the legitimate and eavesdropper channels, either a one-time pad, wiretap coding, or a combination of both turns out to be capacity-achieving.
{"title":"How to use independent secret keys for secure broadcasting of common messages","authors":"R. Schaefer, A. Khisti, H. Poor","doi":"10.1109/ISIT.2015.7282800","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282800","url":null,"abstract":"The broadcast channel with independent secret keys is studied. In this scenario, a common message has to be securely broadcast to two legitimate receivers in the presence of an eavesdropper. The transmitter shares with each legitimate receiver an independent secret key of arbitrary rate. These keys can either be used as one-time pads to encrypt the common message or can be interpreted as fictitious messages used as randomization resources for wiretap coding. Both approaches are discussed and the secrecy capacity is derived for various cases. Depending on the qualities of the legitimate and eavesdropper channels, either a one-time pad, wiretap coding, or a combination of both turns out to be capacity-achieving.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130596827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282839
Albert No, T. Weissman
We establish two strong senses of universality of logarithmic loss as a distortion criterion in lossy compression: For any fixed length lossy compression problem under an arbitrary distortion criterion, we show that there is an equivalent lossy compression problem under logarithmic loss. In the successive refinement problem, if the first decoder operates under logarithmic loss, we show that any discrete memoryless source is successively refinable under an arbitrary distortion criterion for the second decoder.
{"title":"Universality of logarithmic loss in lossy compression","authors":"Albert No, T. Weissman","doi":"10.1109/ISIT.2015.7282839","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282839","url":null,"abstract":"We establish two strong senses of universality of logarithmic loss as a distortion criterion in lossy compression: For any fixed length lossy compression problem under an arbitrary distortion criterion, we show that there is an equivalent lossy compression problem under logarithmic loss. In the successive refinement problem, if the first decoder operates under logarithmic loss, we show that any discrete memoryless source is successively refinable under an arbitrary distortion criterion for the second decoder.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123359362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282646
D. Ryabko, B. Ryabko
The problem of prediction consists in forecasting the conditional distribution of the next outcome given the past. Assume that the source generating the data is such that there is a stationary predictor whose error converges to zero (in a certain sense). The question is whether there is a universal predictor for all such sources, that is, a predictor whose error goes to zero if any of the sources that have this property is chosen to generate the data. This question is answered in the negative, contrasting a number of previously established positive results concerning related but smaller sets of processes.
{"title":"Predicting the outcomes of every process for which an asymptotically accurate stationary predictor exists is impossible","authors":"D. Ryabko, B. Ryabko","doi":"10.1109/ISIT.2015.7282646","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282646","url":null,"abstract":"The problem of prediction consists in forecasting the conditional distribution of the next outcome given the past. Assume that the source generating the data is such that there is a stationary predictor whose error converges to zero (in a certain sense). The question is whether there is a universal predictor for all such sources, that is, a predictor whose error goes to zero if any of the sources that have this property is chosen to generate the data. This question is answered in the negative, contrasting a number of previously established positive results concerning related but smaller sets of processes.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"256 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123359552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282682
Richard G. Wood, T. Linder, S. Yüksel
Optimal zero-delay coding (quantization) of a finite-state Markov source is considered. Building on our earlier work and previous literature, using a stochastic control problem formulation, the existence and structure of optimal quantization policies are studied. Our main result establishes, for infinite horizon problems, the optimality of deterministic and stationary (Walrand-Varaiya type) Markov coding policies. In addition, the ε-optimality of finite-memory quantizers is established and the dependence between the memory length and ε is quantified. Numerical results are also presented.
{"title":"Optimality of Walrand-Varaiya type policies and approximation results for zero delay coding of Markov sources","authors":"Richard G. Wood, T. Linder, S. Yüksel","doi":"10.1109/ISIT.2015.7282682","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282682","url":null,"abstract":"Optimal zero-delay coding (quantization) of a finite-state Markov source is considered. Building on our earlier work and previous literature, using a stochastic control problem formulation, the existence and structure of optimal quantization policies are studied. Our main result establishes, for infinite horizon problems, the optimality of deterministic and stationary (Walrand-Varaiya type) Markov coding policies. In addition, the ε-optimality of finite-memory quantizers is established and the dependence between the memory length and ε is quantified. Numerical results are also presented.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123653036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282673
Erik C. Johnson, Douglas L. Jones, R. Ratnam
In the nervous system, sensory neurons encode signals as a sequence of action potentials (spikes). However, spike generation is metabolically expensive. Achieving high coding fidelity may require a high spike rate. Here we propose that neurons achieve a trade-off by optimally timing spikes so that maximum fidelity is achieved for a given spike rate. The proposed neural encoder generates spikes which are reconstructed by a linear filter, with energy modeled as a constraint proportional to the average spike-rate. We develop expressions for the encoding error and derive the optimal parameters in the limit of high spike-firing rates. The energy-constrained neural encoder is compared with experimental spike-times from two sensory neurons, one cortical and one peripheral. The proposed energy-constrained neural encoder closely approximates the experimentally recorded spike-times, and the decoded experimental inputs are within 2dB of the predicted distortion-energy curve for both neurons.
{"title":"Minimum squared-error, energy-constrained encoding by adaptive threshold models of neurons","authors":"Erik C. Johnson, Douglas L. Jones, R. Ratnam","doi":"10.1109/ISIT.2015.7282673","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282673","url":null,"abstract":"In the nervous system, sensory neurons encode signals as a sequence of action potentials (spikes). However, spike generation is metabolically expensive. Achieving high coding fidelity may require a high spike rate. Here we propose that neurons achieve a trade-off by optimally timing spikes so that maximum fidelity is achieved for a given spike rate. The proposed neural encoder generates spikes which are reconstructed by a linear filter, with energy modeled as a constraint proportional to the average spike-rate. We develop expressions for the encoding error and derive the optimal parameters in the limit of high spike-firing rates. The energy-constrained neural encoder is compared with experimental spike-times from two sensory neurons, one cortical and one peripheral. The proposed energy-constrained neural encoder closely approximates the experimentally recorded spike-times, and the decoded experimental inputs are within 2dB of the predicted distortion-energy curve for both neurons.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114220674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282925
Zhong Zheng, Lu Wei, R. Speicher, R. Müller, Jyri Hämäläinen, J. Corander
The Diversity-Multiplexing Tradeoff (DMT) is studied for the large Rayleigh product channel at non-asymptotic SNRs. The first result is that, as matrix dimensions growing to infinity, the channel capacity converges to a Gaussian random variable. Based on this, we derive a compact expression for the finite-SNR DMT. From the analytical and numerical results, we gain useful insight into the fundamental tradeoff of the considered channel model in the realistic SNR regime.
{"title":"On the finite-SNR Diversity-Multiplexing Tradeoff in large Rayleigh product channels","authors":"Zhong Zheng, Lu Wei, R. Speicher, R. Müller, Jyri Hämäläinen, J. Corander","doi":"10.1109/ISIT.2015.7282925","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282925","url":null,"abstract":"The Diversity-Multiplexing Tradeoff (DMT) is studied for the large Rayleigh product channel at non-asymptotic SNRs. The first result is that, as matrix dimensions growing to infinity, the channel capacity converges to a Gaussian random variable. Based on this, we derive a compact expression for the finite-SNR DMT. From the analytical and numerical results, we gain useful insight into the fundamental tradeoff of the considered channel model in the realistic SNR regime.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116325602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282762
Yinfei Xu, Jun Chen, Qiao Wang
A single-letter lower bound on the sum rate of multiple description coding with tree-structured distortion constraints is established and is shown to be tight in the quadratic Gaussian case.
建立了具有树结构失真约束的多重描述编码和速率的单字母下界,并证明了该下界在二次高斯情况下是紧的。
{"title":"On the sum rate of multiple description coding with tree-structured distortion constraints","authors":"Yinfei Xu, Jun Chen, Qiao Wang","doi":"10.1109/ISIT.2015.7282762","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282762","url":null,"abstract":"A single-letter lower bound on the sum rate of multiple description coding with tree-structured distortion constraints is established and is shown to be tight in the quadratic Gaussian case.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121666637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-14DOI: 10.1109/ISIT.2015.7282911
Ligong Wang, G. Wornell, Lizhong Zheng
This paper considers the problem of communication over a discrete memoryless channel subject to the constraint that the probability that an adversary who observes the channel outputs can detect the communication is low. Specifically, the relative entropy between the output distributions when a codeword is transmitted and when no input is provided to the channel must be sufficiently small. For a channel whose output distribution induced by the zero input symbol is not a mixture of the output distributions induced by other input symbols, it is shown that the maximum number of bits that can be transmitted under this criterion scales like the square root of the blocklength. Exact expressions for the scaling constant are also derived.
{"title":"Limits of low-probability-of-detection communication over a discrete memoryless channel","authors":"Ligong Wang, G. Wornell, Lizhong Zheng","doi":"10.1109/ISIT.2015.7282911","DOIUrl":"https://doi.org/10.1109/ISIT.2015.7282911","url":null,"abstract":"This paper considers the problem of communication over a discrete memoryless channel subject to the constraint that the probability that an adversary who observes the channel outputs can detect the communication is low. Specifically, the relative entropy between the output distributions when a codeword is transmitted and when no input is provided to the channel must be sufficiently small. For a channel whose output distribution induced by the zero input symbol is not a mixture of the output distributions induced by other input symbols, it is shown that the maximum number of bits that can be transmitted under this criterion scales like the square root of the blocklength. Exact expressions for the scaling constant are also derived.","PeriodicalId":272313,"journal":{"name":"2015 IEEE International Symposium on Information Theory (ISIT)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114816685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}