Biomedical EngineeringThis is an RSS file. You can use it to subscribe to this data in your favourite RSS reader, such as GoogleReader, or to display this data on your own website or blog. Subscribe to this data using MyMedWorm.Subscribe to this data using GoogleReader.Subscribe to this data using Bloglines.Subscribe to this data using MyYahoo.

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Editorial BoardEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - November 20, 2009 Category: Biomedical Engineering Source Type: journals

IEEE Signal Processing Society InformationEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

2009 Index IEEE Transactions on Signal Processing Vol. 57Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

IEEE Transactions on Signal Processing information for authorsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

IEEE Transactions on Signal Processing EdicsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

List of ReviewersEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Block-Wise Estimation of and Compensation for I/Q Imbalance in Direct-Conversion TransmittersEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This correspondence proposes a new technique for accurate estimation and compensation for I/Q imbalance in modulators and demodulators used in direct-conversion radio transmitters. This technique uses the actual in-phase (I) and quadrature (Q) components of the modulated signals at the input and output of the transmitter-under-test for adaptive determination of the modulator and demodulator complex gain imbalances. The accuracy of the new algorithm is carefully assessed and compared to earlier works. The robustness of the algorithm to a number of common practical implementation issues (group delay, DC offset, propagation d...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Robust IWFA for Open-Spectrum CommunicationsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This correspondence considers a wireless open-spectrum communication system with $N$ orthogonal narrowband tones and $K$ users who compete to maximize their individual data rates. The correspondence proposes a robust version of the iterative water-filling algorithm (IWFA) that takes into account potential inaccuracies in the noise-plus-interference levels available at the transmitters. It is shown that, in comparison with the conventional version, the robust IWFA (RIWFA) can lead the users to behave in a less greedy fashion and to collaborate unintentionally in order to increase the network sum-rate. In particular, using a...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Training Design for Repetitive-Slot-Based CFO Estimation in OFDMEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Carrier frequency offset (CFO) estimation is a key challenge in wireless systems employing orthogonal frequency-division multiplexing (OFDM) modulation. Often, CFO estimation is carried out using a preamble made of a number, say $J$ , of repetitive slots (RS). We here focus on the issue of optimal RS preamble design using the CramÉr–Rao bound (CRB) averaged over the channel, which is assumed to be Rayleigh. We show that the optimal value of $J$ is a tradeoff between the multipath diversity gain and the number of unknowns to be estimated. In the case of correlated channel taps, we also show that uniform power ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Blind Symbol Timing Estimation for OFDM/OQAM SystemsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this correspondence, we consider the problem of blind symbol timing (ST) estimation for pulse-shaping orthogonal frequency division multiplexing (OFDM) systems based on offset quadrature amplitude modulation (OQAM). In particular, under the assumption of low signal-to-noise ratio, the joint maximum-likelihood (ML) phase offset and ST estimator for additive white Gaussian noise (AWGN) channel is derived. Since the phase estimate is in closed form, the ST estimate requires a one-dimensional maximization procedure with respect to a continuous parameter. Specifically, the ST estimate depends on both the unconjugate and the ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Semiblind Bussgang Equalization for Sparse ChannelsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this correspondence, we describe a semiblind Bussgang equalization scheme that incorporates the training sequence in a quite direct and flexible fashion. Among others, we discuss how the training sequence can be used to control the Bussgang nonlinearity thus enforcing the convergence of the iterative equalizer design. Moreover, we focus on the case of channels whose impulse response is long but sparse, counteracted by equalizers designed on a suitable sparse support. Numerical performance analysis conducted on compact and sparse time-varying channels shows that sparse Bussgang semiblind equalizer using a short training ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

On Low Complexity Robust Beamforming With Positive Semidefinite ConstraintsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This paper addresses the problem of robust beamforming for general-rank signal models with norm bounded uncertainties in the desired and received signal covariance matrices as well as positive semidefinite constraints on the covariance matrices. Two novel minimum variance robust beamformers are derived in closed-form. The first one basically is the closed-form version of an existing iterative algorithm, while the second one offers even better performance with respect to the first one. Both of them have the advantage of low complexity. The effectiveness and performance improvement of the proposed beamformers are verified by...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Design of Directional Filter Banks With Arbitrary Number of SubbandsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This correspondence proposes a novel method for designing directional filter banks (DFBs) with arbitrary number of subbands. Its key feature is the ability to decompose images into arbitrary directionally oriented subbands. The proposed approach is based on the pseudo-polar Fourier transform (PPFT) and one-dimensional (1-D) filter banks (FBs). We take some modifications on the PPFT and then employ 1-D FBs to the modified PPFT. With these operations, the two-dimensional (2-D) DFBs are obtained and the design of them is converted to that of 1-D FBs plus a modified PPFT. Since the number of channels of 1-D FBs can be arbitrar...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Comment on “Parity-Check Matrix Calculation for Paraunitary Oversampled DFT Filter Banks”Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In a previous paper, Karp, Kieffer, and Duhamel have presented three methods to calculate the parity-check matrix of paraunitary oversampled DFT filter banks. Here is another. (Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Widely Linear Estimation Algorithms for Second-Order Stationary SignalsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Recursive estimation algorithms for discrete complex-valued second-order stationary signals are derived following a widely linear processing approach. The formulation is very general in that it allows for a variety of estimation problems. The results are applied on a simulation example and a performance analysis is presented. (Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Mobile Positioning Problem in Manhattan-Like Urban Areas: Uniqueness of Solution, Optimal Deployment of BSs, and Fuzzy ImplementationEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this paper, the problem of mobile positioning in a Manhattan-like urban area is considered. For this area, the involved base stations (BSs) try to use the received distance data to position the mobile station (MS) of interest, which naturally leads to an algebraic problem. However, the concerned problem is analyzed from a geometrical point of view. Using this approach, it is found that the ability to uniquely determine the location of the MS by the knowledge of the positions of BSs and the received Manhattan distances is closely related to the positions of the MS and BSs. The uniqueness issue of mobile position is then ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Error-Resilient Low-Power Viterbi Decoder ArchitecturesEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Three low-power Viterbi decoder (VD) architectures are presented in this paper. In the first, limited decision errors are introduced in the add-compare-select units (ACSUs) of a VD to reduce their critical path delays so that they can be operated at lower supply voltages without incurring timing errors. Power savings in this design can reach 58% and 44% with a 0.15 dB coding loss under reduced voltage operation and process variations, respectively, with adaptive supply voltage and adaptive body biasing applied to avoid timing errors. In the other two designs, we permit data-dependent timing errors to occur whenever a criti...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Mapping Equivalence for Symbolic Sequences: Theory and ApplicationsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We present strong and weak equivalence properties and rely on signal correlation to characterize equivalent mappings. We derive theoretical results which establish conditions for consistency among numerical mappings of symbolic data. Furthermore, we introduce an abstract mapping model for symbolic sequences and extend the notion of equivalence to an algebraic framework. Finally, we illustrate our theoretical results by application to DNA sequence analysis. (Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Efficient Batch and Adaptive Approximation Algorithms for Joint Multicast Beamforming and Admission ControlEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Wireless multicasting is becoming increasingly important for efficient distribution of streaming media and location-aware services to mobile and hand-held devices, network management, and software updates over cellular (UMTS-LTE) and indoor/outdoor wireless networks (e.g., 802.11/16). Multicast beamforming was recently proposed as a means of exploiting the broadcast nature of the wireless medium to boost spectral efficiency and meet Quality of Service (QoS) requirements. Infeasibility is a key issue in this context, due to power or mutual interference limitations. We therefore consider the joint multicast beamforming and a...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Robust Cognitive Beamforming With Bounded Channel UncertaintiesEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This paper studies the robust beamforming design for a multi-antenna cognitive radio (CR) network, which transmits to multiple secondary users (SUs) and coexists with a primary network of multiple users. We aim to maximize the minimum of the received signal-to-interference-plus-noise ratios (SINRs) of the SUs, subject to the constraints of the total SU transmit power and the received interference power at the primary users (PUs) by optimizing the beamforming vectors at the SU transmitter based on imperfect channel state information (CSI). To model the uncertainty in CSI, we consider a bounded region for both cases of chann...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Finite Precision Analysis for Space-Time DecodingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Low complexity optimal (or nearly optimal) decoders for space-time codes have recently been under intensive investigation. For example, recent works by Sirianunpiboon and others show that the Silver code and the Golden code can be decoded optimally (or nearly optimally) with quadratic decoding complexity. Fast decodability makes them very attractive in practice. In implementing these decoders, floating-point to fixed-point conversion (FFC) needs to be carefully undertaken to minimize hardware cost while retaining decoding performance. The process of quantization for fixed-point representations is often ignored by research ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

A Joint Source and Relay Power Allocation Scheme for a Class of MIMO Relay SystemsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
A joint power allocation (PA) scheme for a class of MIMO relay systems is presented in this paper. Based on the maximization of the capacity or minimization of the mean-square error (MSE), two joint PA optimization problems are first formulated. Since the cost functions thus obtained are in general not convex, a tight lower bound of the capacity and a similar upper bound of the MSE are derived, and employed to modify the two cost functions so as to obtain a convex optimization problem. It is confirmed through computer simulations that the proposed PA scheme outperforms the existing method in terms of both the capacity and ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

A Unified Framework for Optimizing Linear Nonregenerative Multicarrier MIMO Relay Communication SystemsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this paper, we develop a unified framework for linear nonregenerative multicarrier multiple-input multiple-output (MIMO) relay communications in the absence of the direct source–destination link. This unified framework classifies most commonly used design objectives such as the minimal mean-square error and the maximal mutual information into two categories: Schur-concave and Schur-convex functions. We prove that for Schur-concave objective functions, the optimal source precoding matrix and relay amplifying matrix jointly diagonalize the source–relay–destination channel matrix and convert the multic...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Correlation Matching Approach for Spectrum Sensing in Open Spectrum CommunicationsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this study, we propose three new procedures that are able to sense the known spectrum of the candidate or primary user, fulfilling the requirements of open spectrum scenarios. These procedures are developed by following the framework of correlation matching, changing the traditional single frequency scan to a spectral scan with a particular shape and generalizing filter-bank designs. The proposed techniques are called Candidate methods, because their goal is to react only when the candidate's spectral shape is present. First, Candidate-F is proposed as a spectral detection method, where this is based on minimizing the F...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Efficient Implementation of Quasi- Maximum-Likelihood Detection Based on Semidefinite RelaxationEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this paper we develop two quasi-maximum likelihood (ML) channel detectors for multiuser detection: semidefinite relaxation (SDR) detector and phase-shift-keying (PSK) detector. These detectors can deliver near-ML bit error rate (BER) performance with a polynomial worst-case complexity. The SDR detector for binary-phase-shift-keying (BPSK) constellation is based on a convex SDR, whereas the PSK detector for $M$-PSK constellations is based on a nonconvex low-rank SDR. The SDR detector is implemented using a dual-scaling interior-point method, while the PSK detector is based on a coordinate descent strategy on a feasible r...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Parametric Dictionary Design for Sparse CodingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This paper introduces a new dictionary design method for sparse coding of a class of signals. It has been shown that one can sparsely approximate some natural signals using an overcomplete set of parametric functions. A problem in using these parametric dictionaries is how to choose the parameters. In practice, these parameters have been chosen by an expert or through a set of experiments. In the sparse approximation context, it has been shown that an incoherent dictionary is appropriate for the sparse approximation methods. In this paper, we first characterize the dictionary design problem, subject to a constraint on the ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Minimum Bayes Risk Adaptive Linear EqualizersEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This paper introduces Bayes risk (expected loss) as a criterion for linear equalization. Since the probability of error is equal to the Bayes risk (BR) for a particular binary loss function, this work is a natural generalization of previous works on minimum probability of error (PE) equalizers. Adaptive equalization algorithms are developed that minimize the BR. Like the minimum PE equalizers, the BR algorithms have low computational complexity which is comparable to that of the LMS algorithm. The advantage of the BR criterion is that the loss function can be specified in a manner that accelerates adaptive equalizer conver...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Ranging Energy Optimization for Robust Sensor Positioning Based on Semidefinite ProgrammingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Sensor positioning is an important task of location-aware wireless sensor networks. In most sensor positioning systems, sensors and beacons need to emit ranging signals to each other. Sensor ranging energy should be low to prolong system lifetime, but sufficiently high to fulfill prescribed accuracy requirements. This motivates us to investigate ranging energy optimization problems. We address ranging energy optimization for an unsynchronized positioning system, which features robust sensor positioning (RSP) in the sense that a specific accuracy requirement is fulfilled within a prescribed service area. We assume a line-of...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Information Theoretic Feature Extraction for Audio-Visual Speech RecognitionEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The problem of feature selection has been thoroughly analyzed in the context of pattern classification, with the purpose of avoiding the curse of dimensionality. However, in the context of multimodal signal processing, this problem has been studied less. Our approach to feature extraction is based on information theory, with an application on multimodal classification, in particular audio–visual speech recognition. Contrary to previous work in information theoretic feature selection applied to multimodal signals, our proposed methods penalize features for their redundancy, achieving more compact feature sets and bet...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Adaptive Constrained Learning in Reproducing Kernel Hilbert Spaces: The Robust Beamforming CaseEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This paper establishes a new paradigm for convexly constrained adaptive learning in reproducing kernel Hilbert spaces (RKHS). Although the technique is of a general nature, we present it in the context of the beamforming problem. A priori knowledge, like beampattern specifications and constraints concerning robustness against steering vector errors, takes the form of multiple closed convex sets in a high (possibly infinite) dimensional RKHS. Every robustness constraint is shown to be equivalent to a min-max optimization task formed by means of the robust statistics $epsilon$ -insensitive loss function. Such a multiplicity ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

An Algorithm to Compute Averages on Matrix Lie GroupsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Averaging is a common way to alleviate errors and random fluctuations in measurements and to smooth out data. Averaging also provides a way to merge structured data in a smooth manner. The present paper describes an algorithm to compute averages on matrix Lie groups. In particular, we discuss the case of averaging over the special orthogonal group of matrices, the unitary group of matrices and the group of symmetric positive-definite matrices. (Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Sequential Unfolding SVD for Tensors With Applications in Array Signal ProcessingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This paper contributes to the field of higher order $(N>2)$ tensor decompositions in signal processing. A novel PARATREE tensor model is introduced, accompanied with Sequential Unfolding SVD (SUSVD) algorithm. SUSVD, as the name indicates, applies a matrix singular value decomposition sequentially on the unfolded tensor reshaped from the right hand basis vectors of the SVD of the previous mode. The consequent PARATREE model is related to the well known family of PARAFAC tensor decomposition models. Both of them describe a tensor as a sum of rank-1 tensors, but PARATREE has several advantages over PARAFAC, when it is applie...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Signal Reconstruction Errors in Jittered SamplingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
One of the most significant types of error in digital signal processing (DSP) systems working with wideband signals is the error introduced by the analog-to-digital (AD) and digital-to-analog (DA) converters. This paper presents an accurate and simple method to evaluate the performance of AD/DA converters affected by clock jitter, which is based on the analysis of the mean square error (MSE) between the reconstructed signal and the original one. Using an approximation of the linear minimum MSE (LMMSE) filter as reconstruction technique, we derive analytic expressions of the MSE. In particular, through asymptotic analysis, ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Complete Characterization of Stable Bandlimited Systems Under Quantization and ThresholdingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this paper, we analyze the approximation behavior of sampling series, where the sample values—taken equidistantly at Nyquist rate—are disturbed either by the nonlinear threshold operator or the nonlinear quantization operator. We perform the analysis for several spaces of bandlimited signals and completely characterize the spaces for which an approximation is possible. Additionally, we study the approximation of outputs of stable linear time-invariant systems by sampling series with disturbed samples for signals in ${cal PW}_{pi}^{1}$. We show that there exist stable systems that become unstable under thre...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Recovering Sparse Signals With a Certain Family of Nonconvex Penalties and DC ProgrammingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This paper considers the problem of recovering a sparse signal representation according to a signal dictionary. This problem could be formalized as a penalized least-squares problem in which sparsity is usually induced by a $ell _{1}$-norm penalty on the coefficients. Such an approach known as the Lasso or Basis Pursuit Denoising has been shown to perform reasonably well in some situations. However, it was also proved that nonconvex penalties like the pseudo $ell _{q}$-norm with $q≪ 1$ or smoothly clipped absolute deviation (SCAD) penalty are able to recover sparsity in a more efficient way than the Lasso. Several a...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Generic Weighted Filtering of Stochastic SignalsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this paper, a new theory of optimal weighted nonlinear filtering is presented. Two filter models are considered. The first model is based on a representation of the filter in the polynomial-like form with $q$ terms where each term consists of weighted matrices and the matrix determined from the error minimization problem. The second model extends the first one to the case of the filter concatenation. The filter models are given in terms of pseudo-inverse matrices, i.e., the requirement of invertibility for covariance matrices is omitted. Thus, our filters always exist. We develop methods which allow us to exploit advant...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Robust Reduced-Rank Adaptive Algorithm Based on Parallel Subgradient Projection and Krylov SubspaceEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this paper, we propose a novel reduced-rank adaptive filtering algorithm exploiting the Krylov subspace associated with estimates of certain statistics of input and output signals. We point out that, when the estimated statistics are erroneous (e.g., due to sudden changes of environments), the existing Krylov-subspace-based reduced-rank methods compute the point that minimizes a “wrong” mean-square error (MSE) in the subspace. The proposed algorithm exploits the set-theoretic adaptive filtering framework for tracking efficiently the optimal point in the sense of minimizing the “true” MSE in t...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Vector Time-Frequency AR Models for Nonstationary Multivariate Random ProcessesEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We introduce the vector time-frequency autoregressive (VTFAR) model for a parsimonious parametric description of nonstationary vector random processes. The VTFAR model generalizes the recently proposed scalar TFAR model to the multivariate case. It is physically meaningful because nonstationarity and spectral correlation are represented in terms of frequency shifts, and it is parsimonious for the practically relevant class of underspread vector processes (i.e., nonstationary vector processes with rapidly decaying correlation in time and frequency). For vector processes with decaying correlation across the signals, we intro...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Sinusoidal Polynomial Parameter Estimation Using the Distribution DerivativeEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this paper, we present a method to estimate the parameters of a generalized sinusoidal model. A generalized sinusoid $x$ is defined as a polynomial in the log domain, with complex coefficients $alpha_{i}$ : $x(t)=exp(sum_{i} alpha_{i} t^i)$, where $i=0cdots Q$. The method is based on the distribution derivative of the signal and operates in the transform domain. The method is very general and can use any linear transform such as the Fourier transform or the wavelet transform, or even combinations of linear transforms. Examples with the Fourier transform are given. The Fourier-based estimation methods are evaluated using...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

A SURE Approach for Digital Signal/Image Deconvolution ProblemsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this paper, we are interested in the classical problem of restoring data degraded by a convolution and the addition of a white Gaussian noise. The originality of the proposed approach is twofold. First, we formulate the restoration problem as a nonlinear estimation problem leading to the minimization of a criterion derived from Stein's unbiased quadratic risk estimate. Secondly, the deconvolution procedure is performed using any analysis and synthesis frames that can be overcomplete or not. New theoretical results concerning the calculation of the variance of the Stein's risk estimate are also provided in this work. Sim...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

An Approximately Efficient TDOA Localization Algorithm in Closed-Form for Locating Multiple Disjoint Sources With Erroneous Sensor PositionsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This paper considers the problem of time difference-of-arrival (TDOA) source localization when the TDOA measurements from multiple disjoint sources are subject to the same sensor position displacements from the available sensor positions. This is a challenging problem and closed-form solution with good localization accuracy has yet to be found. This paper proposes an estimator that can achieve this purpose. The proposed algorithm jointly estimates the unknown source and sensor positions to take the advantage that the TDOAs from different sources have the same sensor position displacements. The joint estimation is a highly ...
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Free Electronic Access to SP PublicationsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

IEEE Transactions on Signal Processing publication informationEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Table of contentsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Signal Processing)
Source: IEEE Transactions on Signal Processing - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Methods for Compensating for Variable Electrode Contact in EITEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Electrical impedance tomography (EIT) is an imaging modality that currently shows promise for the detection and characterization of breast cancer. A very significant problem in EIT imaging is the proper modeling of the interface between the body and the electrodes. We have found empirically that it is very difficult, in a clinical setting, to assure that all electrodes make satisfactory contact with the body. In addition, we have observed a capacitive effect at the skin/electrode boundary that is spatially heterogeneous. To compensate for these problems, we have developed a hybrid nonlinear–linear reconstruction alg...
Source: IEEE Transactions on Biomedical Engineering - November 19, 2009 Category: Biomedical Engineering Source Type: journals

A Tissue Framework for Simulating the Effects of Gastric Electrical Stimulation and In Vivo ValidationEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Gastric pacing is used to modulate normal or abnormal gastric slow-wave activity for therapeutic purposes. New protocols are required that are optimized for motility outcomes and energy efficiency. A computational tissue model was developed, incorporating smooth muscle and interstitial cell of Cajal layers, to enable predictive simulations of slow-wave entrainment efficacy under different pacing frequencies. Concurrent experimental validation was performed via high-resolution entrainment mapping in a porcine model (bipolar pacing protocol: 2 mA amplitude; 400 ms pulsewidth; 17-s period; midcorpus). Entrained gastric slow-w...
Source: IEEE Transactions on Biomedical Engineering - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Table of ContentsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Biomedical Engineering)
Source: IEEE Transactions on Biomedical Engineering - November 19, 2009 Category: Biomedical Engineering Source Type: journals

IEEE Transactions on Biomedical Engineering publication informationEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
(Source: IEEE Transactions on Biomedical Engineering)
Source: IEEE Transactions on Biomedical Engineering - November 19, 2009 Category: Biomedical Engineering Source Type: journals

Fabrication of monodisperse, large-sized, functional biopolymeric microspheres using a low-cost and facile microfluidic device.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We report a novel and facile method for fabricating coaxial microfluidic devices processing various dimensions at low cost, in which polypropylene hollow fibers or glass capillaries are used as the tip of the dispersed phase injection tube. With this coaxial microfluidic device, monodisperse biocompatible microspheres ranging from 300 to 800 mum were obtained by collecting oil-in-water or water-in-oil emulsions and solidifying the suspended microspheres. Microsphere size could be controlled by changing the tips or tuning the concentrations of the dispersed and continuous phases. By adding functional nanoparticles into the ...
Source: Biomedical Microdevices - November 19, 2009 Category: Biomedical Engineering Authors: Zhu L, Li Y, Zhang Q, Wang H, Zhu M Tags: Biomed Microdevices Source Type: journals