{"title":"Approaching Optimal Performance By Lattice-Reduction Aided Soft Detectors","authors":"Wei Zhang, Xiaoli Ma","doi":"10.1109/CISS.2007.4298422","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298422","url":null,"abstract":"Lattice reduction (LR) technique has been introduced into the process of linear equalization to improve the performance. It has been shown that LR-aided hard detectors collect full diversity with low complexity for many transmission systems. However, though LR-aided linear equalizers collect the same diversity as that collected by the maximum-likelihood (ML) detector, there still exists a performance gap between LR-aided and ML equalizers. To fill this gap, one may use soft detectors. In this paper, we give two LR-aided soft detectors with different candidates generation methods. We compare the performance and complexity of our algorithms with the existing alternatives and show that our methods can achieve near-optimal performance. The performance-complexity tradeoff of our proposed algorithms is also studied. Simulation results validate the effectiveness of our algorithms.","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129025112","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":"Wireless Multicasting with Channel Uncertainty","authors":"Jie Luo, A. Ephremides","doi":"10.1109/CISS.2007.4298418","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298418","url":null,"abstract":"We consider wireless multicasting where a source of common information is transmitted to a group of receivers over block fading channels. Communication between the transmitter and each of the receivers is implemented by specifying a minimum signal to noise plus interference ratio (SINR) threshold; if the threshold is met, the communication is successful at a corresponding rate, otherwise the communication fails. Such error controlled reception converts wireless channels into erasure channels, upon which forward error correction or retransmission is concatenated to achieve reliable communication. Assuming only channel distribution information at the transmitter, we derive the optimal SINR threshold given the transmit power constraint. We show, in the low transmit power regime, the optimal ratio between the SINR threshold and the transmit power is determined only by the channel distributions.","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132787525","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 Power Sensor Network for Identification of Heterogeneous Wireless Networks","authors":"Goran Ivkovic, P. Spasojevic, I. Seskar","doi":"10.1109/CISS.2007.4298411","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298411","url":null,"abstract":"We consider a scenario with multiple radio sources operating in the 2.4GHz ISM band and emitting signals that may overlap in time and frequency. Each source is characterized by an on/off signal, which represents its activity in time. Sources are modelled as statistically independent if they belong to different networks or statistically dependent if they belong to the same network, in which case they produce signals that do not overlap in time. A network of sensors performs measurements, where each sensor measures average received power with some time granularity. We show how source activity signals can be recovered from the power measurements using blind signal separation techniques. Recovered signals are partitioned into groups where each group is formed of non overlapping signals in time that belong to the same network.","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133158638","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 New Design Paradigm for MIMO Dispersive Channel DF Equalizer","authors":"D. Mattera, F. Palmieri","doi":"10.1109/CISS.2007.4298421","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298421","url":null,"abstract":"We consider the issue of the equalizer design in a modern block-adaptive application scenario where the receiver processing power allows us to implement the filters, designed according to an indirect approach, by using a software logical structure. We propose a new design paradigm that, unlike the classical one, counts that the filter structure is not defined in hardware and can be, therefore, modified in correspondence of each new channel estimation. An important step of the proposed paradigm concerns the choice of the most suited implementation structure for the equalizer filters; such a solution obviously depends on the constraints imposed to the implementation quality parameters (e.g., implementation delay, computational complexity, memory requirements); moreover, the most suited solution also depends on the channel impulse response as well as on signal and noise spectra and, therefore, it is useful to be able to modify it in a time-varying wireless scenario. In particular, when at least one external filter pole is sufficiently close to the unit circle, the forward-backward implementation of the ideal noncausal filter (often discarded in the equalizer design) can provide significant reduction in computational complexity over all alternative filter structures.","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133397910","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}
Ido Nevat, A. Wiesel, Jinhong Yuan, Yonina C. Eldar
{"title":"Maximum A-Posteriori Estimation in Linear Models With a Gaussian Model Matrix","authors":"Ido Nevat, A. Wiesel, Jinhong Yuan, Yonina C. Eldar","doi":"10.1109/CISS.2007.4298274","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298274","url":null,"abstract":"We consider the Bayesian inference of a random Gaussian vector in a linear model with a Gaussian model matrix. We derive the maximum a-posteriori (MAP) estimator for this model and show that it can be found using a simple line search over a unimodal function that can be efficiently evaluated. Next, we discuss the application of this estimator in the context of near-optimal detection of near-Gaussian-digitally modulated signals and demonstrate through simulations that the MAP estimator outperforms the standard linear MMSE estimator in terms of mean square error (MSE) and bit error rate (BER).","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133488019","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":"Consensus Estimation via Belief Propagation","authors":"H. Dai, Yanbing Zhang","doi":"10.1109/CISS.2007.4298313","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298313","url":null,"abstract":"In this paper, a new problem, consensus estimation, is formulated, whose setting is complementary to the well-known CEO problem. In particular, a set of nodes are employed to sense and estimate a common source, and the purpose is to reach the best possible estimate for all nodes, through local processing and information exchange over the network. The belief propagation algorithm is adopted to provide a common information processing and dissemination framework for such a purpose. The discussion is also extended to the application of estimating a Markov random field.","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133032523","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":"Power Allocation for Multi-Antenna Multiple Access Channels in Cognitive Radio Networks","authors":"Lan Zhang, Yan Xin, Ying-Chang Liang","doi":"10.1109/CISS.2007.4298327","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298327","url":null,"abstract":"A cognitive radio network is often described as a secondary communication network operating in a frequency band originally allocated to a primary network consisting of one or multiple primary users. A fundamental challenge for realizing such a system is to ensure the quality of service of the primary users as well as to maximize the throughput of the secondary users. In this paper, we consider a sum-rate maximization problem for single-input multiple output multiple access channels (SIMO-MAC) under interference constraints for the primary users as well as a peak transmission power constraint for each secondary user. We apply zero-forcing based decision feedback equalizers to decouple the SIMO-MAC, and develop a capped water-filling algorithm to maximize the sum-rate of the secondary users. We also investigate another scenario where only multiple primary users' interference constraints are considered. Furthermore, we provide numerical simulations to illustrate the effectiveness of the algorithm.","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114054429","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 Mean Convergence Analysis for Partial Update NLMS Algorithms","authors":"Jinhong Wu, M. Doroslovački","doi":"10.1109/CISS.2007.4298268","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298268","url":null,"abstract":"This paper discusses the convergence rates of partial update normalized least mean square (NLMS) algorithms for long, finite impulse response (FIR) adaptive filters. We specify the general form of convergence of tap weight vector's mean deviation for white Guassian input, and analyze several best known partial update algorithms' performance. These results are compared with the conventional NLMS algorithm. We further discuss the similarity in update effects of some partial update algorithms and proportionate-type NLMS algorithms. This theoretically demonstrates that for sparse impulse response system identification with white Guassian input, properly designed partial update NLMS algorithms, although need only a fraction of the fully updated NLMS algorithm's computational power, have the potential of achieving better performance than conventional NLMS.","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122958280","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":"Lossless Compression-Based Steganalysis of LSB Embedded Images","authors":"C. Boncelet, L. Marvel","doi":"10.1109/CISS.2007.4298442","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298442","url":null,"abstract":"A new method of steganalysis for images with embedded messages is presented. We consider two embedding methods: least significant bit (LSB) replacement and plusmn1 LSB embedding. Our method uses lossless image compression to generate statistics that are fed into a support vector machine classifier. We compare results against the pairs method, one of the best existing LSB steganalysis methods. Both our method and pairs performs well for LSB replacement. However, while pairs cannot detect plusmn1 LSB embedding at all, our method can.","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116933034","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":"Cooperation Strategies for Two Co-located receivers, with no CSI at the transmitter","authors":"A. Sanderovich, A. Steiner, S. Shamai","doi":"10.1109/CISS.2007.4298325","DOIUrl":"https://doi.org/10.1109/CISS.2007.4298325","url":null,"abstract":"We study the case of a single transmitter, which communicates to two co-located users, through an independent block Rayleigh fading channel. The co-location nature of the users allows cooperation, which increases the overall achievable rate, from the transmitter to both users. The transmitter is ignorant of the fading coefficients, while receivers have access to perfect channel state information (CSI). This gives rise to the broadcast approach used by the transmitter. The broadcast approach facilitates reliable transmission rates adapted to the actual channel conditions, designed to maximize average throughput. With the broadcast approach, users can decode partly the total message, with almost any fading realization. The better the channel quality, the more layers that can be decoded. Such an approach is useful when considering average rates, rather than outage vs. rate (outage never occurs). The cooperation between the users is performed over the co-location channel, modeled as separated additive white Gaussian channels (AWGN), with an average power constraint, and limited or unlimited bandwidth. New achievable rates when combining cooperation with the broadcasting approach are presented, where through simple change of power allocation, substantial gains are demonstrated. We consider both amplify-and-forward (AF) and Wyner-Ziv compress-and-forward (CF), as cooperation approaches, and also compare to decode-and-forward (DF). We extend these methods using the broadcast approach, and also to include separated processing of the layers, realized through multi-session cooperation. Further, novel closed form expressions for infinitely many multi-session AF and recursive expressions for the more complex multi-session CF are given. Numerical results for the various cooperation strategies demonstrate the efficiency of multi-session cooperation. Our results can be extended straightforwardly to a setting of a single transmitter sending common information for two users.","PeriodicalId":151241,"journal":{"name":"2007 41st Annual Conference on Information Sciences and Systems","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127387696","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}