2007 IEEE International Symposium on Information Theory最新文献_第3页

Cycle Analysis and Construction of Protographs for QC LDPC Codes With Girth Larger Than 12 周长大于12的QC LDPC码的循环分析及原型图的构造

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557555

Sunghwan Kim, Jong-Seon No, Habong Chung, Dong-joon Shin

引用次数: 14

Signal Processing Algorithms to Decipher Brain Function 破译大脑功能的信号处理算法

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557073

E. Brown

{"title":"Signal Processing Algorithms to Decipher Brain Function","authors":"E. Brown","doi":"10.1109/ISIT.2007.4557073","DOIUrl":"https://doi.org/10.1109/ISIT.2007.4557073","url":null,"abstract":"these capabilities is limited severely by the scarcity of the two principal resources in wireless networks, namely energy and bandwidth. Much of the capacity growth of the past two decades has been enabled by major advances in the wireless physical layer. However, in recent years, attention has turned increasingly to the higher network layers to examine interactions among nodes that can lead to even greater efficiencies in the use of wireless resources. This talk examines two types of such interactions: competition among nodes in multiple-access communication networks, and collaboration among nodes in wireless sensor networks. In the first context, the network is viewed as an economic system, in which terminals behave as agents competing for radio resources to optimize the energy efficiency with which they transmit messages. A game theoretic formalism is used to analyze the effects of various design choices and quality-of-service constraints on energy efficiency. In the second context, collaborative techniques for optimizing the use of radio resources in sensor networks are considered. Here, the focus is primarily on distributed inference, in which distinctive features of wireless sensor networks can be exploited through collaboration among nodes to effect a tradeoff between inferential accuracy and energy consumption.","PeriodicalId":193467,"journal":{"name":"2007 IEEE International Symposium on Information Theory","volume":"40 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124670464","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}

引用次数: 0

Fast Control over Fiber Memory 光纤存储器的快速控制

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557580

S. Li, X. Tan

引用次数: 3

On the Gaussian MIMO Wiretap Channel 关于高斯MIMO窃听信道

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557590

A. Khisti, G. Wornell, A. Wiesel, Yonina C. Eldar

{"title":"On the Gaussian MIMO Wiretap Channel","authors":"A. Khisti, G. Wornell, A. Wiesel, Yonina C. Eldar","doi":"10.1109/ISIT.2007.4557590","DOIUrl":"https://doi.org/10.1109/ISIT.2007.4557590","url":null,"abstract":"Wyner's wiretap channel is generalized to the case when the sender, the receiver and the eavesdropper have multiple antennas. We consider two cases: the deterministic case and the fading case. In the deterministic case, the channel matrices of the intended receiver and the eavesdropper are fixed and known to all the nodes. In the fading case, the channel matrices experience block fading and the sender has only the intended receiver's channel state information (CSI) and statistical knowledge of the eavesdropper's channel. For the deterministic case, a scheme based on the generalized-singular-value-decomposition (GSVD) of the channel matrices is proposed and shown to achieve the secrecy capacity in the high signal-to-noise-ratio (SNR) limit. When the intended receiver has only one antenna (MISO case) the secrecy-capacity is characterized for any SNR. Next, a suboptimal \"artificial noise\" based scheme is considered. Its performance is characterized and observed to be nearly optimal in the high SNR regime for the MISO case. This scheme extends naturally to the fading case and results are reported for the MISO case. For the independent Rayleigh fading distribution as we simultaneously increase the number of antennas at the sender and the eavesdropper, the secrecy capacity approaches zero if and only if the ratio of the number of eavesdropper antennas to transmitter antennas is at least two.","PeriodicalId":193467,"journal":{"name":"2007 IEEE International Symposium on Information Theory","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126706213","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}

引用次数: 220

Complex Near-Orthogonal Designs with No Zero Entry 无零入口的复近正交设计

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557616

Gopu V. R. Muni Kumar, B. Rajan

引用次数: 2

Sequential Decoding with a Look-Ahead Path Metric 具有前瞻性路径度量的顺序解码

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557568

M. Sikora, D. Costello

{"title":"Sequential Decoding with a Look-Ahead Path Metric","authors":"M. Sikora, D. Costello","doi":"10.1109/ISIT.2007.4557568","DOIUrl":"https://doi.org/10.1109/ISIT.2007.4557568","url":null,"abstract":"Convolutional codes are an efficient means of achieving reliable communication with low latency and complexity constraints. Since optimal Viterbi decoding of long (say, above 8) constraint length codes can be prohibitively complex, sequential decoders, such as the Zigangirov-Jelinek (ZJ) stack algorithm or the Fano algorithm can be applied. However, the performance of sequential algorithms is limited by a steep increase in the average number of steps per information bit that takes place close to the cutoff rate, more than by the error correcting capabilities of the code itself. In this paper we examine the problem of improving the performance of sequential decoders by designing more sophisticated path metrics. In particular, we propose a look-ahead (LA) path metric, which equals the Fano metric of the best path stemming from the current path for a fixed number of time steps. We demonstrate that in the limit of a large number of look-ahead time steps, sequential decoding becomes equivalent to the backtracking step of the Viterbi algorithm. Direct computation of the LA metric requires searching an exponential number of partial paths at each state and is infeasible, since the extra cost of computing the metric outweighs the savings in the number of time steps. However, in some scenarios of interest, the LA metric can be computed by other means. In the particular case of a covolutional code transmitted over a binary symmetric channel (BSC), this metric can be obtained from a modified syndrome decoder that stores for each partial syndrome the weight of the minimum weight error event. We demonstrate through simulations that this structure leads to an efficient and computationally inexpensive sequential decoding algorithm.","PeriodicalId":193467,"journal":{"name":"2007 IEEE International Symposium on Information Theory","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114372584","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}

引用次数: 1

Characterization of max-min fair performance in large networks via Szemeredi's Regularity Lemma 利用Szemeredi正则引理表征大型网络中最大最小公平性能

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557218

M. Wiczanowski, H. Boche, S. Stańczak

引用次数: 3

Constellation Design via Capacity Maximization 基于容量最大化的星座设计

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557486

M. Barsoum, Christopher R. Jones, M. Fitz

{"title":"Constellation Design via Capacity Maximization","authors":"M. Barsoum, Christopher R. Jones, M. Fitz","doi":"10.1109/ISIT.2007.4557486","DOIUrl":"https://doi.org/10.1109/ISIT.2007.4557486","url":null,"abstract":"Traditional constellations are uniformally spaced. By giving up uniform spacing, constellations can be designed to have larger joint (i.e. overall) capacity or parallel decoding capacity. In this paper non-uniformally spaced (i.e. 'geometrically' shaped) constellations are designed to maximize either of these quantities. By way of numerical capacity computations we show that except in special cases, there are no universally optimal geometrically shaped constellations across all code rates, and that the optimization of a constellation has to target a specific code rate. Unlike joint capacity, optimizing for parallel decoding capacity is label dependent. For PAM and PSK constellations, we found the maximum parallel decoding capacity to be achieved using gray (not necessarily binary reflective gray) labels. However, for PAM constellations, not all gray labels can yield the highest parallel decoding capacity. Besides the conventional use of a (log2 (M) -1) /log2 (M) code rate with an M-point constellation for bandwidth efficient communications, the optimized constellations could offer further non-trivial gains at lower code rates (unlike traditional constellations). An optimized constellation is used with a state-of-the-art LDPC code and simulation results are presented. This paper also draws a distinction between probabilistic shaping and geometric shaping and in fact proves under broad conditions, that any gain in capacity which can be found via probabilistic shaping can also be achieved or exceeded solely through geometric shaping.","PeriodicalId":193467,"journal":{"name":"2007 IEEE International Symposium on Information Theory","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122260732","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}

引用次数: 66

On the Burnashev exponent for Markov channels 关于马尔可夫通道的Burnashev指数

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557494

G. Como, S. Yüksel, S. Tatikonda

引用次数: 1

N-Shift Cross-Orthogonal Sequences and Complete Complementary Codes n移交叉正交序列与完全互补码

2007 IEEE International Symposium on Information Theory Pub Date : 2007-06-24 DOI: 10.1109/ISIT.2007.4557612

Chenggao Han, N. Suehiro, T. Hashimoto

引用次数: 21