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# 1997 IEEE International Conference on Acoustics, Speech, and Signal Processing

## Filter Results

Displaying Results 1 - 25 of 187
• ### 1997 IEEE International Conference On Acoustics, Speech, And Signal Processing

Publication Year: 1997, Page(s):iii - xv
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• ### Blind adaptive equalization and diversity combining

Publication Year: 1997, Page(s):4041 - 4044 vol.5
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Spatial-temporal equalizer can be used in the wireless communication systems with antenna arrays to improve the performance. We introduce two blind adaptive algorithms for spatial-temporal equalization, and present their convergence. Computer simulation demonstrates that the new algorithms converge faster than the fractionally spaced constant-modulus algorithm (FS-CMA). View full abstract»

• ### Author index

Publication Year: 1997, Page(s):A1 - A26
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• ### Blind 2D RAKE receiver for CDMA incorporating code synchronization and multipath time delay estimation

Publication Year: 1997, Page(s):4025 - 4028 vol.5
Cited by:  Papers (9)
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A novel wideband beamforming technique for cellular CDMA systems is presented. The proposed algorithm asymptotically provides the optimum combination of space-time samples to maximize the SINR for the signal with the desired code (SDC) by optimally combining its multipath and canceling strong multiuser access interference (MUAI). In contrast to previously proposed techniques, code synchronization ... View full abstract»

• ### Blind source separation using time-frequency distributions: algorithm and asymptotic performance

Publication Year: 1997, Page(s):3469 - 3472 vol.5
Cited by:  Papers (11)
| | PDF (328 KB)

This paper addresses the problem of the blind source separation which consists of recovering a set of signals of which only instantaneous linear mixtures are observed. A blind source separation approach exploiting the difference in the time-frequency (t-f) signatures of the sources is considered. The approach is based on the diagonalization of a combined set of spatial time-frequency distribution... View full abstract»

• ### A generalized array manifold model for local scattering in wireless communications

Publication Year: 1997, Page(s):4021 - 4024 vol.5
Cited by:  Papers (19)  |  Patents (17)
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In wireless communication scenarios, local scatterers in the vicinity of the mobile sources cause angular spreading. As a result, the spatial signatures will not belong to the conventional array manifold parameterized by direction of arrival (DOA) alone. A parameterized model for spatial signatures applicable in scenarios with local scattering is presented. Several algorithms that exploit this mod... View full abstract»

• ### Second-order blind identifiability of certain classes of multipath channels using antenna arrays

Publication Year: 1997, Page(s):3465 - 3468 vol.5
Cited by:  Papers (2)
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Recently, a number of classes of multipath channels which are not blindly identifiable from fractionally spaced samples and second-order cyclic spectra have been presented. In this paper, we consider the blind identification problem of these channels using multiple antennas and show that they will not in general give rise to any common roots among the sub-channels formed from the antennas, and hen... View full abstract»

• ### Asymptotic performance of blind antenna array receiver algorithms for CDMA

Publication Year: 1997, Page(s):4017 - 4020 vol.5
Cited by:  Papers (2)
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This paper considers the performance of four channel identification techniques for code division multiple access (CDMA) antenna array receivers. These techniques are based on the assumption that the interference is spatially white: they provide a spatial “matched filter” solution. Perturbation formulae are presented for estimating the attainable signal to interference and noise ratios ... View full abstract»

• ### A test statistic for sequential identification of co-channel digital signals using a deflation approach

Publication Year: 1997, Page(s):3461 - 3464 vol.5
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When sequentially separating a linear combination of co-channel digital signals, it is necessary at each step to test the validity of the currently estimated signal prior to proceeding to extract the next one. We describe a procedure for use with sequential algorithms which uses a deflation-based approach combined with a simple test statistic. The deflation step removes the contributions of the cu... View full abstract»

• ### Total least squares linear prediction for frequency estimation with frequency weighting

Publication Year: 1997, Page(s):3993 - 3996 vol.5
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This paper presents a general total least squares (GTLS) solution for linear prediction to estimate closely spaced sinusoids. It is found that the TLS prediction error is not a good criterion to provide a robust solution. In this paper, a frequency weighted prediction error approach is introduced. Experimental results show that the GTLS solution based on the frequency weighted prediction error can... View full abstract»

• ### Wavelet transform based detection of photon-limited and low contrast objects

Publication Year: 1997, Page(s):3657 - 3660 vol.5
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This paper presents methods for detection and localization of photon-limited objects in noise. As opposed to the correlation based or Fourier transform based techniques which exhibit sensitivity to object scaling, we propose a method based on the continuous wavelet transform with its ability to reject noise and to localize objects in space and time as well as in scale. An advantageous twist presen... View full abstract»

• ### Sensor array calibration using measured steering vectors of uncertain location

Publication Year: 1997, Page(s):3749 - 3752 vol.5
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We present a maximum likelihood approach for calibrating sensor arrays in the presence of mutual coupling, channel gain and phase mismatch and array geometry uncertainties using measured steering vectors of uncertain locations. The estimated perturbation parameters is used to calibrate the array manifold, hence enabling many high resolution array processing algorithms to attain their potential adv... View full abstract»

• ### Robust source detection in shallow water

Publication Year: 1997, Page(s):3705 - 3708 vol.5
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It is not possible, in practice, to precisely model a complex propagation channel, such as shallow water. This lack of accuracy causes a deterioration in the performance of the optimal detector and motivates the search for sub-optimal detectors which are insensitive to uncertainties in the propagation model. We present a novel, robust detector, which measures the degree of spatial-stationarity of ... View full abstract»

• ### Using PHiPAC to speed error back-propagation learning

Publication Year: 1997, Page(s):4153 - 4156 vol.5
Cited by:  Papers (4)
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We introduce PHiPAC, a coding methodology for developing portable high-performance numerical libraries in ANSI C. Using this methodology, we have developed code for optimized matrix multiply routines. These routines can achieve over 90% of peak performance on a variety of current workstations, and are often faster than vendor-supplied optimized libraries. We then describe the bunch-mode back-propa... View full abstract»

• ### A new multichannel blind equalization criterium based on a generalized Rayleigh quotient

Publication Year: 1997, Page(s):3457 - 3460 vol.5
Cited by:  Papers (3)
| | PDF (312 KB)

Recent works have presented novel techniques that exploit cyclostationarity for channel identification (equalization) in data communication systems using only second order statistics. In particular, the feasibility of blind identification based on the forward shift' structure of the correlation matrices of the source has been shown. In this paper we propose an alternative algorithm based on this ... View full abstract»

• ### Semi-blind second order identification of convolutive channels

Publication Year: 1997, Page(s):3905 - 3908 vol.5
Cited by:  Papers (40)  |  Patents (1)
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Our contribution addresses the identification of multiple convolutive FIR channels. Many recently proposed blind techniques suffer from the imperfect knowledge of the channel order. Meanwhile the major part of the existing communication systems requires periodically transmitted reference sequences known at the reception site. This information can be used to ensure the robustness the existing blind... View full abstract»

• ### On moments of complex Wishart and complex inverse Wishart distributed matrices

Publication Year: 1997, Page(s):3817 - 3820 vol.5
Cited by:  Papers (5)
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This paper addresses the calculation of moments of complex Wishart and complex inverse Wishart distributed random matrices. Complex Wishart and complex inverse Wishart distributed random matrices are used in applications like radar, sonar, or seismology in order to model the statistical properties of complex sample covariance matrices and complex inverse sample covariance matrices, respectively. T... View full abstract»

• ### Distinction between polynomial phase signals with constant amplitude and random amplitude

Publication Year: 1997, Page(s):3653 - 3656 vol.5
Cited by:  Papers (6)
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In this paper we propose to distinguish between constant amplitude polynomial phase signals and the ones having random amplitude. We study four possibilities for the modulating process. We show that the distinction of this kind of signals is not always possible when using the polynomial phase transform. In fact, in some applications, we show that we cannot estimate the phase of the signal with thi... View full abstract»

• ### A state space model for H∞ type array signal processing

Publication Year: 1997, Page(s):3745 - 3748 vol.5
Cited by:  Papers (1)
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The idea of applying H∞ estimation techniques to the “array uncertainties problem” is motivated by the fact that H∞ estimation is robust to model uncertainties and lack of statistical information with respect to noise. A new state space model for the received signal of a general array of sensors is developed which, in contrast to existing models, is ca... View full abstract»

• ### Higher order blind source separation using the cyclostationarity property of the signals

Publication Year: 1997, Page(s):4061 - 4064 vol.5
Cited by:  Papers (5)  |  Patents (1)
| | PDF (368 KB)

Over the last decade, a great number of higher order (HO) blind source separation methods have been developed, aiming at separating several statistically independent sources without any a priori information about the latter. A performance analysis of some of these methods has shown that the latter perform very well in a great number of situations encountered in radiocommunication contexts but fail... View full abstract»

• ### Detection of multipath random signals by multiresolution subspace design

Publication Year: 1997, Page(s):3701 - 3704 vol.5
Cited by:  Papers (2)
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In our earlier work, we developed a robust detector for multipath constrained environments when the transmitted signal is known. In this paper, we extend these results to the case where the transmitted signal is a random process. The approach of Chaung He et al. (see ICASSP, p.V-2650-53, 1996 and IEEE Trans. Signal Processing, 1996) is to replace the orthogonal projection on the multipath signal s... View full abstract»

• ### A family of fixed-point algorithms for independent component analysis

Publication Year: 1997, Page(s):3917 - 3920 vol.5
Cited by:  Papers (64)
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Independent component analysis (ICA) is a statistical signal processing technique whose main applications are blind source separation, blind deconvolution, and feature extraction. Estimation of ICA is usually performed by optimizing a `contrast' function based on higher-order cumulants. It is shown how almost any error function can be used to construct a contrast function to perform the ICA estima... View full abstract»

• ### Parallel bit-stream neurohardware for blind separation of sources

Publication Year: 1997, Page(s):4149 - 4152 vol.5
Cited by:  Papers (1)
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The use of digital stochastic computing is proposed to realize a recurrent network for blind separation of undelayed linearly superposed signals into their original components. The stochastic representation of signals allows one to design very simple digital processing elements to implement all the operations necessary for the algorithm of Herault and Jutten (1986). A first hardware implementation... View full abstract»

• ### Signal estimation using wavelet-Markov models

Publication Year: 1997, Page(s):3429 - 3432 vol.5
Cited by:  Papers (4)
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Current wavelet-based statistical signal and image processing techniques such as shrinkage and filtering treat the wavelet coefficients as though they were statistically independent. This assumption is unrealistic; considering the statistical dependencies between wavelet coefficients can yield substantial performance improvements. We develop a new framework for wavelet-based signal processing that... View full abstract»

• ### On detection of double talk and changes in the echo path using a Markov modulated channel model

Publication Year: 1997, Page(s):3869 - 3872 vol.5
Cited by:  Papers (4)  |  Patents (4)
| | PDF (348 KB)

This paper addresses the problem of detection and discrimination of the two phenomena, double talk and echo path change, in a telephone channel. It is of uttermost importance to quickly detect a change in the echo path while not confusing it with double talk, since the echo canceller should react differently whether an echo path change or double talk has occurred. Novel algorithms of low complexit... View full abstract»