Prize-Collecting Data Fusion for Cost-Performance Tradeoff in Distributed Inference (2009)
Animashree An, Meng Wang, Lang Tong, Ananthram Swami
Abstract—A novel formulation for optimal sensor selection and in-network fusion for distributed inference known as the prizecollecting data fusion (PCDF) is proposed in terms of optimal tradeoff...
1 Energy Scaling Laws for Distributed Inference in Random Fusion Networks (2009)
Animashree An, Student Member, Joseph E. Yukich, Lang Tong, Ananthram Swami
Abstract—The energy scaling laws of multihop data fusion networks for distributed inference are considered. The fusion network consists of randomly located sensors distributed i.i.d. according to a...
Energy Scaling Laws for Distributed Inference in Random Networks (2009)
Animashree An, Joseph E. Yukich, Lang Tong, Ananthram Swami
Abstract—The energy scaling laws of multihop data fusion networks for distributed inference are considered. The fusion network consists of randomly located sensors independently distributed...
Detection of Gauss–Markov Random Fields With Nearest-Neighbor Dependency (2009)
Animashree An, Student Member, Lang Tong, Ananthram Swami
Abstract—The problem of hypothesis testing against independence for a Gauss–Markov random field (GMRF) is analyzed. Assuming an acyclic dependency graph, an expression for the log-likelihood...
Power Control in Cognitive Radio Networks: How to Cross a Multi-Lane Highway (2009)
Wei Ren, Qing Zhao, Ananthram Swami
We consider power control in cognitive radio networks where secondary users identify and exploit instantaneous and local spectrum opportunities without causing unacceptable interference to primary...
Networking Cognitive Radios for Dynamic Spectrum Access (2009)
� Physical layer issues � MAC layer issues � Network layer issues
Joint Scale-Lag Diversity in Wideband Mobile Direct Sequence Spread Spectrum Systems (2009)
Adam R. Margetts, Philip Schniter, Senior Member, Ananthram Swami, Senior Member
Abstract — We consider the effect of mobility on a wideband direct sequence spread spectrum (DSSS) communication system, and study a scale-lag Rake receiver capable of leveraging the diversity that...
Optimal Node Density for Detection in Energy Constrained Random Networks (2009)
Animashree Anandkumar, Lang Tong, Ananthram Swami
The problem of optimal node density maximizing the Neyman-Pearson detection error exponent subject to a constraint on average (per node) energy consumption is analyzed. The spatial correlation among...
Non-Scalable Nature of Layered Architecture Routing: Shortest Path Raw Data: Yn (2009)
Anima Anandkumar, Lang Tong, Ananthram Swami, Anthony Ephremides, Yn [y, Avg Cost
Routing Cost along link (i, j) = dist(i, j) 2
Cost-Performance Tradeoff in Multi-hop Aggregation for Statistical Inference (2009)
Animashree An, Lang Tong, Ananthram Swami, Anthony Ephremides
Abstract—The problem of distributed fusion for binary hypothesis testing in a multihop network is considered. The sensor measurements are spatially correlated according to a Markov random field...
Connectivity of Cognitive Radio Networks: Proximity vs. Opportunity (2009)
Ren, Wei, Zhao, Qing, Cheowtirakul, Drasvin, Swami, Ananthram
We address the connectivity of large-scale ad hoc cognitive radio networks. We introduce the concept of connectivity region defined as the set of density pairs (the density of secondary users and the...
Bursty Traffic in Energy-Constrained Opportunistic Spectrum Access (2009)
Yunxia Chen, Qing Zhao, Ananthram Swami
Opportunistic spectrum access (OSA) is one of the approaches envisioned for dynamic spec-trum management [1]. It has received increasing attention due to its compatible with the current spectrum...
Prize-Collecting Data Fusion for Cost-Performance Tradeoff (2009)
Animashree An, Meng Wang, Lang Tong, Ananthram Swami
A novel formulation for optimal sensor selection and in-network fusion for distributed inference known as the prize-collecting data fusion (PCDF) is proposed in terms of optimal tradeoff between the...
Estimation de ruptures multiples dans les processus FARIMA (2009)
COULON, Martial, CHABERT, Marie, SWAMI, Ananthram
On s'intéresse à la détection de ruptures dans les processus FARIMA. La procédure d'estimation de ruptures combine l'estimateur temps-échelle du paramètre de longue dépendance, l'estimation du...
Joint Design for Opportunistic Spectrum Access with A. Network Model Multi-Channel Sensing (2008)
Yunxia Chen, Qing Zhao, Ananthram Swami, I. Problem Statement, B. A Constrained, Pomdp Formulation
Consider a spectrum of N orthogonal channels licensed to a slotted primary network. Let Sn(t) ∈ {0 (busy), 1 (idle)} denote the occupancy of channel n in slot t. We assume that the spectrum...
ON THE EFFECT OF ASYMMETRIC COMMUNICATION ON DISTRIBUTED TIME SYNCHRONIZATION (2008)
Prabir Barooah, João P. Hespanha, Ananthram Swami
Abstract — Several distributed algorithms have been recently proposed to estimate clock offsets and skews in a network of processors from a set of noisy measurements of the difference between clock...
Yunxia Chen, Qing Zhao, Ananthram Swami
Opportunistic spectrum access (OSA) that allows secondary users to independently search for and exploit instantaneous spectrum availability is considered. The design objective is to maximize the...
Power Control in Cognitive Radio Networks: How to Cross a Multi-Lane Highway (2008)
Ren, Wei, Zhao, Qing, Swami, Ananthram
We consider power control in cognitive radio networks where secondary users identify and exploit instantaneous and local spectrum opportunities without causing unacceptable interference to primary...
Energy Scaling Laws for Distributed Inference in Random Fusion Networks (2008)
Anandkumar, Animashree, Yukich, Joseph E., Tong, Lang, Swami, Ananthram
The energy scaling laws of multihop data fusion networks for distributed inference are considered. The fusion network consists of randomly located sensors distributed i.i.d. according to a general...
Hamid R. Sadjadpour, Robert Ulman, Ananthram Swami, Anthony Ephremides, Hamid R. Sadjadpour, Robert Ulman, ...
open access articles distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly...
Cross-Layer Design of Opportunistic Spectrum Access in the Presence of Sensing Error (2008)
Qing Zhao, Lang Tong, Ananthram Swami, Yunxia Chen
Abstract — We address the design of cognitive MAC protocols for opportunistic spectrum access in the presence of sensing error. Decentralized protocols are presented for ad hoc networks where there...
OPTIMAL TRAINING OVER THE GAUSS-MARKOV FADING CHANNEL: A CUTOFF RATE ANALYSIS (2008)
Saswat Misra, Ananthram Swami, Lang Tong
We consider the problem of optimal allocation of resources between training and data for transmission over a Gauss-Markov fading channel. Inaccurate channel state information (CSI) is available at...
Decentralized Cognitive MAC for Opportunistic Spectrum Access in Ad Hoc Networks: (2008)
A Pomdp Framework, Qing Zhao, Lang Tong, Ananthram Swami, Yunxia Chen
Abstract — We propose decentralized cognitive MAC protocols that allow secondary users to independently search for spectrum opportunities without a central coordinator or a dedicated communication...
Cutoff Rate Optimal Binary Inputs with Imperfect CSI (2008)
Saswat Misra, Ananthram Swami, Senior Member, Lang Tong, Senior Member
Abstract — We use the cutoff rate to study the optimal binary input distributions for the Rayleigh flat-fading channel with imperfect receiver channel state information (CSI). First, we evaluate...
Quantization for Maximin ARE in Distributed Estimation (2008)
Parvathinathan Venkitasubramaniam, Student Member, Lang Tong, Ananthram Swami, Senior Member
Abstract—We consider the design of optimal quantizers for the distributed estimation of a deterministic parameter. In particular, we design deterministic scalar quantizers to maximize the minimum...
Rong, Yue, Hua, Yingbo, Swami, Ananthram, Swindlehurst, A. Lee
A space-time optimal power schedule for multiple distributed multiple-input multiple-output (MIMO) links without the knowledge of the instantaneous channel state information (CSI) at the transmitting...
Minimum Cost Data Aggregation with Localized Processing for Statistical Inference (2008)
Animashree An, Lang Tong, Ananthram Swami
The problem of minimum cost in-network fusion of measurements, collected from distributed sensors via multihop routing is considered. A designated fusion center performs an optimal...
Minimum Cost Data Aggregation with Localized Processing for Statistical Inference (2008)
Animashree An, Lang Tong, Ananthram Swami, Anthony Ephremides
Abstract—The problem of minimum cost in-network fusion of measurements, collected from distributed sensors via multihop routing is considered. A designated fusion center performs an optimal...
Distributed Estimation Via Random Access (2008)
Animashree Anandkumar, Lang Tong, Ananthram Swami
In this correspondence, the problem of distributed Bayesian estimation is considered in the context of a wireless sensor network. The Bayesian estimation performance is analyzed in terms of the...
Minimum Cost Data Aggregation with Localized Processing for Statistical Inference (2008)
Animashree Anandkumar, Lang Tong, Ananthram Swami, Anthony Ephremides
The problem of minimum cost in-network fusion of measurements, collected from distributed sensors via multihop routing is considered. A designated fusion center performs an optimal...
Energy Scaling Laws for Distributed Inference in Random Networks (2008)
Animashree Anandkumar, Joseph E. Yukich, Lang Tong, Ananthram Swami
The energy scaling laws of multihop data fusion networks for distributed inference are considered. The fusion network consists of randomly located sensors independently distributed according to a...
Optimal Node Density for Detection in Energy-Constrained Random Networks (2008)
Animashree Anandkumar, Lang Tong, Ananthram Swami
The problem of optimal node density maximizing the Neyman-Pearson detection error exponent subject to a constraint on average (per node) energy consumption is analyzed. The spatial correlation among...
Detection of Gauss-Markov Random Fields with Nearest-Neighbor Dependency (2008)
Animashree Anandkumar, Lang Tong, Ananthram Swami
The problem of hypothesis testing against independence for a Gauss-Markov random field (GMRF) is analyzed. Assuming an acyclic dependency graph, an expression for the log-likelihood ratio of...
Blind Channel Estimation for Space-Time Coded WCDMA (2007)
Youngchul Sung, Lang Tong, Ananthram Swami
A new blind channel estimation technique is proposed for space-time coded wideband CDMA systems using aperiodic and possibly multirate spreading codes. Using a decorrelating front-end, the received...
Multipath Delay Estimation for Frequency Hopping Systems (2007)
Prashanth H, Ananthram Swami, Lang Tong, Lang Tong
The multipath delay estimation problem for a slow frequency hopping system is studied. High resolution delay estimation algorithms are proposed by exploiting in-variance structures in the data...
Shengli Zhou, Georgios B. Giannakis, Ananthram Swami
We compare single user digital Ivlulti-Carrier Spread Spectrum modulation with Direct Sequence Spread Spectrum in the presence of frequency-selective multipath fading. We derive closed-form...
Detection of Gauss-Markov Random Fields with Nearest-Neighbor Dependency (2007)
Anandkumar, Animashree, Tong, Lang, Swami, Ananthram
The problem of hypothesis testing against independence for a Gauss-Markov random field (GMRF) is analyzed. Assuming an acyclic dependency graph, an expression for the log-likelihood ratio of...
Chen, Yunxia, Zhao, Qing, Swami, Ananthram
We address the design of opportunistic spectrum access (OSA) strategies that allow secondary users to independently search for and exploit instantaneous spectrum availability. Integrated in the joint...
Wireless Mobile Ad Hoc Networks (2007)
Hamid R. Sadjadpour, Robert Ulman, Ananthram Swami, Anthony Ephremides
Distributed and Cooperative Link Scheduling for Large-Scale Multihop Wireless Networks (2007)
Kezhu Hong, Yingbo Hua, Ananthram Swami
A distributed and cooperative link-scheduling (DCLS) algorithm is introduced for large-scale multihop wireless networks. With this algorithm, each and every active link in the network cooperatively...
Spectrum Opportunity Detection: How Good is Listen-before-Talk (2007)
Qing Zhao, Wei Ren, Ananthram Swami
Abstract—We consider spectrum opportunity detection in cognitive radio networks for spectrum overlay. We highlight the differences between detecting primary signals and detecting spectrum...
Joint PHY-MAC design for opportunistic spectrum access in the presence of sensing errors (2007)
Yunxia Chen, Qing Zhao, Ananthram Swami
We address the design of opportunistic spectrum access (OSA) strategies that allow secondary users to independently search for and exploit instantaneous spectrum availability. The design objective is...
Wireless Mobile Ad Hoc Networks (2007)
Hamid R. Sadjadpour, Robert Ulman, Ananthram Swami, Anthony Ephremides
Distributed and Cooperative Link Scheduling for Large-Scale Multihop Wireless Networks (2007)
Kezhu Hong, Yingbo Hua, Ananthram Swami
A distributed and cooperative link-scheduling (DCLS) algorithm is introduced for large-scale multihop wireless networks. With this algorithm, each and every active link in the network cooperatively...
Distributed Spectrum Sensing and Access in Cognitive Radio Networks with Energy Constraint (2007)
Yunxia Chen, Qing Zhao, Ananthram Swami
We design distributed spectrum sensing and access strategies for opportunistic spectrum access (OSA) under an energy constraint on secondary users. Both the continuous and the bursty traffic models...
Distributed detection and estimation in decentralized sensor networks: and overview (2006)
Sergio Barbarossa, Gesualdo Scutari, Ananthram Swami
In this work we review some of the most recent in-network computation capabilities that can be used in sensor networks to alleviate the information traffic from the sensors towards the sink nodes....
Optimal training for time-selective wireless fading channels using cutoff rate (2006)
Saswat Misra, Ananthram Swami, Lang Tong
We consider the optimal allocation of resources—power and bandwidth—between training and data transmissions for singleuser time-selective Rayleigh flat-fading channels under the cutoff rate...
Minimax Quantization for Distributed Maximum Likelihood Estimation,” submitted to (2006)
Parvathinathan Venkitasubramaniam, Lang Tong, Ananthram Swami
We consider the design of quantizers for the distributed estimation of a deterministic parameter, when the fusion center uses a Maximum-Likelihood estimator. We define a new metric of performance,...
Reliable Communications over Rapidly Time-Varying Channels (2006)
Geert Leus, Georgios Giannakis, Jean-Paul Linnartz, Xiaoli Ma, Ananthram Swami, Cihan Tepedelenlioğlu
Optimal Training for Time-Selective Wireless Fading Channels Using Cutoff Rate (2006)
Saswat Misra, Ananthram Swami, Lang Tong
We consider the optimal allocation of resources—power and bandwidth—between training and data transmissions for single-user time-selective Rayleigh flat-fading channels under the cutoff rate...
Asymptotic Locally Optimal Detector for Large Scale Sensor Networks Under the Poisson Regime (2005)
Sung, Youngchul, Tong, Lang, Swami, Ananthram
We consider distributed detection with a large number of identical binary sensors deployed over a region where the phenomenon of interest (POI) has spatially varying signal strength. Each sensor...
Bandwidth and Power Efficiency Considerations for Optimal Training in OFDM (2005)
Ning Chen, G. Tong Zhou, Ananthram Swami
OFDM has been adopted by many high speed transmission standards. Pilot tone assisted modulation (PTAM) is a well known technique to estimate the channel state information (CSI) in OFDM but is not...
Quantization for distributed estimation in large scale sensor networks (2005)
Parvathinathan Venkitasubramaniam, Gökhan Mergen, Lang Tong, Ananthram Swami
We study the problem of quantization for distributed parameter estimation in large scale sensor networks. Assuming a Maximum Likelihood estimator at the fusion center, we show that the Fisher...
Blind Channel Estimation for Space-Time Coded WCDMA (2004)
Sung, Youngchul, Tong, Lang, Swami, Ananthram
A new blind channel estimation technique is proposed for space-time coded wideband CDMA systems using aperiodic and possiblymultirate spreading codes. Using a decorrelating front end, the received...
Asymptotic locally optimal detector for large scale sensor networks under the Poisson regime (2004)
Sung, Youngchul, Tong, Lang, Swami, Ananthram
Proceedings of 2004 International Conference Communications, Paris, France
ASYMPTOTIC LOCALLY OPTIMAL DETECTOR FOR LARGE-SCALE SENSOR (2004)
Sung, Youngchul, Tong, Lang, Swami, Ananthram
Proceeding of 2004 International Conference on Acoustics, Speech, and Signal Processing, Montreal, Canada
An Analysis of Optimal Training for Correlated Fading Channels Using Cutoff Rate (2004)
Misra, Saswat, Swami, Ananthram, Tong, Lang
We consider the problem of optimal allocation of resources (power and bandwidth) between training and data for transmission over a Gauss Markov fading channel. Inaccurate channel state information...
Asymptotic locally optimal detector for large-scale sensor networks under the Poisson regime (2004)
Youngchul Sung, Lang Tong, Ananthram Swami
We consider distributed detection with a large number of identical binary sensors deployed over a region where the phenomenon of interest (POI) has spatially varying signal strength. Each sensor...
Asymptotic locally optimal detector for large-scale sensor networks under the Poisson regime (2004)
Youngchul Sung, Lang Tong, Ananthram Swami, Senior Member
Abstract—We consider distributed detection with a large number of identical binary sensors deployed over a region where the phenomenon of interest (POI) has spatially varying signal strength. Each...
Blind Channel Estimation for Space-Time Coded WCDMA (2004)
Youngchul Sung, Lang Tong, Ananthram Swami
A new blind channel estimation technique is proposed for space-time coded wideband CDMA systems using aperiodic and possibly multirate spreading codes. Using a decorrelating front end, the received...
Semiblind Channel Estimation for Space-time Coded WCDMA (2003)
Sung, Y., Tong, L., Swami, Ananthram
A new semiblind channel estimation technique is proposed for space-time coded wideband CDMA systems using aperiodic and possibly multirate spreading codes. Using a decorrelating matched filter, the...
Cutoff rate analysis of the Gauss-Markov fading channel with adaptive energy allocation (2003)
Saswat Misra, Ananthram Swami, Lang Tong
We use the cutoff rate to analyze reliable rates over the firstorder Guass-Markov fading channel when an optimized pilot-symbol assisted modulation (PSAM) scheme is used to provide partial CSI to the...
Cross-layer designs of multichannel reservation MAC under Rayleigh fading (2003)
Atul Maharshi, Lang Tong, Ananthram Swami
We consider a reservation-based medium access control (MAC) scheme where users reserve data channels through a slotted-ALOHA procedure. The base station grants access to users in a Rayleigh fading...
Cross-Layer Designs of Multichannel Reservation MAC under Rayleigh Fading (2003)
Atul Maharshi, Lang Tong, Ananthram Swami, Senior Member, Senior Member
We consider a reservation-based medium access control (MAC) scheme where users reserve data channels through a slotted-ALOHA procedure. The base station grants access to users in a Rayleigh fading...
SEMIBLIND CHANNEL ESTIMATION FOR SPACE-TIME CODED WCDMA (2002)
Sung, Y., Tong, L., Swami, Ananthram
A new semi-blind channel estimation technique is proposed for space-time coded wideband CDMA systems using aperiodic and possibly multirate spreading codes. Exploiting the subspace structure of the...
Shengli Zhou, Student Member, Georgios B. Giannakis, Ananthram Swami, Senior Member
Abstract—We compare single user digital multi-carrier spread spectrum (MC-SS) modulation with direct sequence (DS) SS (with a modified implementation) in the presence of narrowband interference...
Mounir Ghogho, Ananthram Swami, Georgios B. Giannakis
Abstract- We address the problem of frequency synchronization in OFDM-based communications systems in the context of frequency-selective fading channels. Frequency offsets are estimated by inserting...
Least Squares Detection of Multiple Changes in Fractional ARIMA Processes (2001)
Martial Coulon, Ananthram Swami
We address the problem of estimating changes in fractional integrated ARMA (FARIMA) processes. These changes may be in the Long Range Dependence (LRD) parameter or the ARMA parameters. The signal is...
Parameter estimation for random amplitude chirp signals (1999)
Olivier Besson, Mounir Ghogho, Ananthram Swami, Senior Member
Abstract — We consider the problem of estimating the parameters of a chirp signal observed in multiplicative noise, i.e., whose amplitude is randomly time-varying. Two methods for solving this...
CRB’s and estimators for the parameters of time-selective fading channels (1999)
Mounir Ghogho, Ananthram Swami
We consider the problem of estimating the Doppler shift and rate of a linearly modulated digital signal subject to time-selective Rician fading. We derive the Cram'er-Rao bounds for the...
Mounir Ghogho, Asoke K. N, Ananthram Swami, Senior Member, Senior Member
Abstract—The problem of estimating the phase parameters of a phase-modulated signal in the presence of colored multiplicative noise (random amplitude modulation) and additive white noise (both...
Mounir Ghogho, Ananthram Swami, Senior Member, Bernard Garel
Abstract — The problem of estimating the frequencies of harmonics in multiplicative and additive noise is addressed. The cyclic mean (CM) can be used if the multiplicative noise has nonzero mean;...
Nonlinear least-squares estimation for harmonics in multiplicative and additive noise (1999)
Mounir Ghogho, Ananthram Swami, Asoke K. N
We consider the problem of estimating the frequency of a complex harmonic in the presence of additive and multiplicative noise. Two non-linear least-squares (NLLS) estimators, NLLS and NLLS, are...
Analysis of Wavelet Transform Multiscale Products for Step Detection and Estimation (1998)
Sadler, Brian M., Swami, Ananthram
We consider discrete wavelet transform (DWT) multiscale products for detection and estimation of steps. Here the DWT is an overcomplete approximation to smoothed gradient estimation, with smoothing...
Rate-Optimal Signal Design for Wireless Communications (1998)
Misra, Saswat, Swami, Ananthram, Tong, Lang
In a tactical communications scenario, the transmitter will only have an imperfect estimate of the temporally correlated mobile RF channel. Given imperfect channel state information (CSI), we address...
Yunxia Chen, Qing Zhao, Ananthram Swami, I. Problem Statement
Consider a spectrum that consists of N channels (e.g., separated frequency bands), each with bandwidth Bn (n = 1, · · · , N). These N channels are licensed to a primary network whose users...
System identification using cumulants / (1989)
Thesis (Ph. D.)--University of Southern California, 1989.