{"title":"On the distortion-energy tradeoff for zero-delay transmission of a Gaussian source over the AWGN channel","authors":"Erman Koken, E. Tuncel, Deniz Gündüz","doi":"10.1109/ITW.2015.7133170","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133170","url":null,"abstract":"An achievable scheme for zero-delay transmission of an i.i.d. Gaussian source over an additive white Gaussian channel with no bandwidth limitation is introduced, and its energy-distortion performance is analyzed. By the nature of the problem, one must transmit each source sample separately but can use the channel infinitely many times. We introduce an outage concept, and analyze the expected distortion conditioned on no outage. We show that the proposed scheme can approach to the asymptotical decay for large enough energy for arbitrary outage probability. The proposed scheme builds on separation of source and channel coding, whereby the source is quantized with a high-resolution optimal quantizer. In the high energy-to-noise ratio (ENR) regime, the minimum energy required to obtain a given distortion level in the proposed scheme can approach arbitrarily close the Shannon bound, which can only be achieved using infinite delay.","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123730053","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}
{"title":"A constrained-dictionary version of LZ78 asymptotically achieves the finite-state compressibility with a distortion measure","authors":"J. Ziv","doi":"10.1109/ITW.2015.7133077","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133077","url":null,"abstract":"The unrestricted-dictionary type LZ78 universal data-compression algorithm (as well as the LZ77 and LZW versions) achieves asymptotically, as the block-length tends to infinity, the FS compressibility, namely the best compression-ratio that may be achieved by any Information-lossless(IL) block-to-variable finite-state(FS) algorithm, for any infinitely-long individual sequence.","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127656551","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}
{"title":"Lattice index coding for the broadcast channel","authors":"Natarajan Lakshmi Prasad, Y. Hong, E. Viterbo","doi":"10.1109/ITW.2015.7133089","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133089","url":null,"abstract":"The index coding problem involves a sender with K messages to be transmitted across a broadcast channel, and a set of receivers each of which demands a subset of the K messages while having prior knowledge of a different subset as side information. We consider the specific instance of noisy index coding where the broadcast channel is Gaussian and every receiver demands all the messages from the source. We construct lattice index codes for this channel by encoding the K messages individually using K modulo lattice constellations and transmitting their sum modulo a shaping lattice. We introduce a design metric called side information gain that measures the advantage of a code in utilizing the side information at the receivers, and hence its quality as an index code. Based on the Chinese remainder theorem, we then construct lattice index codes for the Gaussian broadcast channel. Among all lattice index codes constructed using any densest lattice of a given dimension, our codes achieve the maximum side information gain.","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"161 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114628596","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}
{"title":"Improved layered regenerating codes characterizing the exact-repair storage-repair bandwidth tradeoff for certain parameter sets","authors":"Kaushik Senthoor, B. Sasidharan, P. V. Kumar","doi":"10.1109/ITW.2015.7133121","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133121","url":null,"abstract":"The characterization of the storage-repair bandwidth tradeoff of (n, k, d)-regenerating codes under the exact-repair setting remains an open problem. The problem has been solved only for the special case of (n, k, d) = (4, 3, 3). In the present paper, we characterize the tradeoff for the larger family of parameters (n, k = 3, d = n - 1). This is accomplished by constructing an (n, k <; d, d)-regenerating code, referred to as the improved layered code. In the case when (n, k = 3, d = n - 1), the code operates on a point that coincides with an interior point of a recently derived outer bound on the tradeoff. The code also achieves an interior point on the outer bound for the parameter set (n, k = 4, d = n - 1).","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131912798","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}
{"title":"Oblivious transfer over OFDM and MIMO channels","authors":"Jithin Ravi, B. Dey, E. Viterbo","doi":"10.1109/ITW.2015.7133112","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133112","url":null,"abstract":"We consider the problem of oblivious transfer (OT) over OFDM and MIMO wireless communication systems where only the receiver knows the channel state information. The sender and receiver also have unlimited access to a noise-free real channel. Using a physical layer approach, based on the properties of the noisy fading channel, we propose a scheme that enables the transmitter to send obliviously one-of-two files, i.e, without knowing which one has been actually requested by the receiver, while also ensuring that the receiver does not get any information about the other file.","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124967032","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}
{"title":"Secure transmission using an untrusted relay with scaled compute-and-forward","authors":"Zhijie Ren, J. Goseling, J. Weber, M. Gastpar","doi":"10.1109/ITW.2015.7133135","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133135","url":null,"abstract":"A two-hop channel is considered, in which the source wants to send information to the destination while keeping the information confidential from the relay. A novel lattice chain and compute-and-forward based scheme is proposed in which the destination provides cooperative jamming. Channel state information is used at the source and the destination to scale the encoding lattices for the message and the jamming signal according to the channel gains. We compare the achievable secrecy rate of our scheme with an upper bound and with the achievable secrecy rate of other schemes. It follows that our scheme outperforms all existing schemes except in the low power region.","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115285329","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}
{"title":"Design of LDPC codes for the q-ary partial erasure channel","authors":"Rami Cohen, Yuval Cassuto","doi":"10.1109/ITW.2015.7133125","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133125","url":null,"abstract":"In this paper, we discuss practical design of low-density parity-check (LDPC) codes for the q-ary partial erasure channel (QPEC). This channel is an extension of the binary erasure channel (BEC), where partial information on the output is available. We provide a linear programming (LP) optimization for the design of good degree distributions, and compare our code design results to codes obtained using an LP optimization formulated for the BEC. We show superior performance in terms of code rate and complexity, when designing an LDPC code for a desired decoding threshold.","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130402071","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}
A. Bhatia, Veeresh Taranalli, P. Siegel, S. Dahandeh, A.R. Krishnan, Patrick Lee, Dahua Qin, Moni Sharma, Teik Yeo
{"title":"Polar codes for magnetic recording channels","authors":"A. Bhatia, Veeresh Taranalli, P. Siegel, S. Dahandeh, A.R. Krishnan, Patrick Lee, Dahua Qin, Moni Sharma, Teik Yeo","doi":"10.1109/ITW.2015.7133166","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133166","url":null,"abstract":"Polar codes provably achieve the capacity of binary memoryless symmetric (BMS) channels with low complexity encoding and decoding algorithms, and their finite-length performance on these channels, when combined with suitable decoding algorithms (such as list decoding) and code modifications (such as a concatenated CRC code), has been shown in simulation to be competitive with that of LDPC codes. However, magnetic recording channels are generally modeled as binary-input intersymbol interference (ISI) channels, and the design of polar coding schemes for these channels remains an important open problem. Current magnetic hard disk drives use LDPC codes incorporated into a turbo-equalization (TE) architecture that combines a soft-output channel detector with a soft-input, soft-output sum-product algorithm (SPA) decoder. An interleaved coding scheme with a multistage decoding (MSD) architecture with LDPC codes as component codes has been proposed as an alternative to TE for ISI channels. In this work, we investigate the use of polar codes as component codes in the TE and MSD architectures. It is shown that the achievable rate of the MSD scheme converges to the symmetric information rate of the ISI channel when the number of interleaves is large. Simulations results comparing the performance of LDPC codes and polar codes in TE and MSD architectures are presented.","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128329452","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}
{"title":"The two-way multi-relay channel","authors":"Jonathan Ponniah, Liang-Liang Xie, P. Kumar","doi":"10.1109/ITW.2015.7133140","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133140","url":null,"abstract":"We propose an achievable decode-forward rate region for the two-way multi-relay network. The region is the outcome of a carefully mediated attempt, through a so-called “reverse-order” ranking policy, to privilege the disadvantaged nodes in the network over the advantaged. We use the word “advantage” in reference to the ability of a node to recover the decode-forward outer-bound by virtue of its position in the network. The proposed rate-region shows promise in recovering most of a decode-forward outer-bound which, due to a fundamental deadlock problem we identify, is not tight. The rate region itself is derived from (n-2)! individual regions, each corresponding to a unique decode-forward scheme, which geometrically fit together into an intelligible whole. The underlying theory, offset encoding, appears to be well suited for multi-source multi-relay networks with bidirectional information flow.","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125504875","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}
{"title":"On adaptive linear programming decoding of ternary linear codes","authors":"E. Rosnes, Michael Helmling","doi":"10.1109/ITW.2015.7133150","DOIUrl":"https://doi.org/10.1109/ITW.2015.7133150","url":null,"abstract":"In this work, we consider adaptive linear programming (LP) decoding of ternary linear codes, i. e., linear codes over the finite field Fq with q = 3 elements. In particular, we characterize completely the codeword polytope (or the convex hull) of the binary image, under Flanagan's embedding, of a ternary single parity-check code. Then, this characterization is used to develop an efficient adaptive LP decoder for ternary codes. Numerical experiments confirm that this decoder is very efficient compared to a static LP decoder and scales well with both block length and check node degree. Finally, we briefly consider the case of nonbinary codes over the finite field Fq with q = 3m elements, where m > 1 is a positive integer.","PeriodicalId":174797,"journal":{"name":"2015 IEEE Information Theory Workshop (ITW)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122168333","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}