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Subspace-Constrained array response Estimation in the Presence of Model Errors

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2021年 69卷 417-427页

作者： Wax, Mati Adler, Amir Technion Israel Inst Technol IL-3200003 Haifa Israel Ort Braude Coll Engn Elect Engn Dept IL-2161002 Karmiel Israel

We present a novel solution to the problem of estimating the array response of the signal of interest (SOI) in case it is constrained to lie in a known subspace, aimed at coping with model errors in the known subspace. The solution is based on a novel formulation of the problem, targeted at matching the error-contaminated model-based signal subspace to its sampled-data counterpart. The solution turns out to minimize the angle between these two subspaces, which is intuitively very pleasing. We solve the problem for three different characterization of the spatial interference: (i) the spatial interference is known, (ii) the spatial interference is unknown, and (iii) the spatial interference is constrained to lie in a known subspace. We present a closed-form solution for the first case and iterative solutions for the other two cases. Based on these solutions, we derive the corresponding estimators for the SOI's waveform and their signal-to-interference+noise ratio (SINR). Simulation results, demonstrating the superiority of the derived solutions over the corresponding deterministic maximum likelihood (DML) solutions, are included.

关键词： Interference Sensor arrays Signal to noise ratio array signal processing Uncertainty Numerical models Data models array response signal subspace subspace errors model errors steering vector errors array manifold errors principal angles angle-between-subspaces

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Directional response of the short vertical line array for the distance source in deep ocean

Directional response of the short vertical line array for th...

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The 2010 International Conference on Computer Application and System Modeling(2010计算机应用与系统建模国际会议 ICCASM 2010)

作者： Tongwei Zhang Kunde Yang College of Marine Northwestern Polytechnical University Xi'an Shaanxi 710072 China

ISBN: (纸本)9781424472352

The arrival signals of the vertical line array (VLA) in the waveguide are not plane waves. The direction of maximum array output will not be the exact direction of the source. The acoustic pressure field can be expressed in terms of a normal mode expansion. The output of the VLA for a distance source in the waveguide is then constructed by summing up contributions of array response to each of the modes weighted in accordance to the normal mode amplitude. The low and high order modes arrive at shallow and steep grazing angles, respectively. In deep ocean, a source away from the sound channel axis couples strongly with high order modes while weakly with low order modes. The direction of maximum output of a short VLA deviates significantly from the horizontal direction.

关键词： array response short vertical line array deep ocean

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The Influence of Spatial Filters on Infrasound array responses

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PURE AND APPLIED GEOPHYSICS 2014年第3-5期171卷 575-585页

作者： Brown, David J. Szuberla, Curt A. L. McCormack, David Mialle, Pierrick Comprehens Nucl Test Ban Treaty Org Int Data Ctr Preparatory Commiss Vienna Int Ctr A-1400 Vienna Austria Univ Alaska Fairbanks Inst Geophys Fairbanks AK 99775 USA Geol Survey Canada Nat Resources Canada Ottawa ON K1A 0Y3 Canada

A spatial filter is often attached to a microphone or microbarometer in order to reduce the noise caused by atmospheric turbulence. This filtering technique is based on the assumption that the coherence length of turbulence is smaller than the spatial extent of the filter, and so contributions from turbulence recorded at widely separated ports will tend to cancel while those of the signal of interest, which will have coherence length larger than the spatial dimensions of the filter, will be reinforced. In this paper, the plane wave response for a spatial filter with an arbitrary arrangement of open ports is determined. It is found that propagation over different port-to-sensor distances causes out-of-phase sinusoids to be summed at the central manifold and can lead to significant amplitude decay and phase delays as a function of frequency. The determined spatial filter plane wave response is superimposed on an array response typical of infrasound arrays that constitute the International Monitoring System infrasound network used for nuclear monitoring purposes. It is found that signal detection capability in terms of the Fisher Statistic can be significantly degraded at certain frequencies. The least-squares estimate of signal slowness can change by up to 1.5A degrees and up to 10 m/s if an asymmetric arrangement of low and high frequency spatial filters is used. However, if a symmetric arrangement of filters is used the least-squares estimate of signal slowness is found to be largely unaffected, except near the predicted null frequency.

关键词： Infrasound spatial filter pipe filter array response

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The modelling of ambient noise due to shipping and wind sources in complex environments

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APPLIED ACOUSTICS 1997年第3期51卷 251-287页

作者： Hamson, RM BAeSEMA Apex Tower 7 High Street New Maiden Surrey UK KT3 4DN

A review of noise modelling techniques is given for shipping and wind noise sources covering the frequency range 50 Hz to 3 kHz and concentrating mainly on work done from 1980 onwards. Propagation mechanisms, sources of input data and a variety of established noise models for both noise sources are described and results presented in terms of horizontal and vertical directionality and the responses of hydrophone arrays. Examples of model validations against measurements taken in complex environments demonstrate that successful noise prediction is possible provided careful modelling of all propagation mechanisms is included. (C) 1997 Elsevier Science Ltd.

关键词： propagation ambient noise shipping wind source levels directionality array response modelling measurements

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Minimising number of perturbed elements in linear and planar adaptive arrays with broad nulls using compressed sensing approach

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IET MICROWAVES ANTENNAS & PROPAGATION 2019年第8期13卷 1134-1141页

作者： El-Khamy, Said E. Korany, Noha O. Abdelhay, Magdy A. Alexandria Univ Elect Engn Dept Alexandria Egypt Alexandria Inst Engn & Technol Elect & Commun Engn Dept Alexandria Egypt

Here, a new algorithm, based on compressed sensing (CS), is presented for generating broad nulls in linear and planar adaptive antenna arrays through the control of only a small number of elements. In particular, sparse recovery theorem and convex optimisation are used to generate the broad nulls by perturbing the complex weights of a minimum number of elements. The problem is first formulated as a sparse recovery problem and then relaxed to the form of a convex optimisation problem. In addition to the nulling constraints, another constraint is added to ensure that the perturbed elements do not cause a pointing error in the synthesised array pattern. Also, one more constraint is used to set a predefined peak value for the array response in the sidelobe region. The optimisation problem is then solved iteratively using the iterative re-weighted $\ell _1$l1 -norm minimisation technique to reduce the number of perturbed array elements to the lowest possible number while satisfying the constraints on the radiation pattern. Simulations were conducted for linear and planar arrays. The results show that the proposed algorithm is capable of forming the required nulls by changing the complex weights of only a small percentage of the array elements.

关键词： adaptive antenna arrays antenna radiation patterns iterative methods array signal processing planar antenna arrays interference suppression direction-of-arrival estimation convex programming antenna arrays linear antenna arrays minimisation optimisation complex weights minimising number perturbed elements planar adaptive arrays broad nulls compressed sensing approach planar adaptive antenna arrays sparse recovery theorem minimum number sparse recovery problem convex optimisation problem nulling constraints synthesised array pattern array response iterative re-weighted $\ell norm minimisation technique perturbed array elements lowest possible number planar arrays required nulls

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A directional acoustic array using silicon micromachined piezoresistive microphones

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JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2003年第1期113卷 289-298页

作者： Arnold, DP Nishida, T Cattafesta, LN Sheplak, M Univ Florida Dept Elect & Comp Engn Interdisciplinary Microsyst Grp Gainesville FL 32611 USA Univ Florida Dept Elect & Comp Engn Dept Mech & Aerosp Engn Gainesville FL 32611 USA

The need for noise source localization and characterization has driven the development of advanced sound field measurement techniques using microphone arrays. Unfortunately, the cost and complexity of these systems currently limit their widespread use. Directional acoustic arrays are commonly used in wind tunnel studies of aeroacoustic sources and may consist of hundreds of condenser microphones. A microelectromechanical system (MEMS)-based directional acoustic array system is presented to demonstrate key technologies to reduce the cost, increase the mobility, and improve the data processing efficiency versus conventional systems. The system uses 16 hybrid-packaged MEMS silicon piezoresistive microphones that are mounted to a printed circuit board. In addition, a high-speed signal processing system was employed to generate the array response in near real time. Dynamic calibrations of the microphone sensor modules indicate an average sensitivity of 831 muV/Pa with matched magnitude (+/-0.6 dB) and phase (+/-1degrees) responses between devices. The array system was characterized in an an-echoic chamber using a monopole source as a function of frequency, sound pressure level, and source location. The performance of the MEMS-based array is comparable to conventional array systems and also benefits from significant cost savings. (C) 2003 Acoustical Society of America.

关键词： .sound pressure printed circuit acoustic arrays microphones using silicon noise source wind tunnel array system array response

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CALIBRATION CASE-STUDY OF NATURAL SOURCE ELECTROMAGNETIC array DATA RECORDED OVER A WELL IN OREGON

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PROCEEDINGS OF THE IEEE 1989年第2期77卷 334-337页

作者： SHOEMAKER, CL SHOHAM, Y HOCKEY, RL SHELL WESTERN EXPLORAT & PROD HOUSTONTX 77001

Experimental results are described for a data acquisition method originally developed by F.X. Bostick (1986) that measures the electric field continuously along a profile. A three step sequence is used in the automated interpretation of electromagnetic (EM) array data. Following some preliminary steps in which an initial model is constructed, each interpretive refinement of the model consists of (1) forward computation of the array response and the numerically evaluated Jacobian, or matrix of first partial derivatives of the response with respect to model parameters; (2) data processing for static removal making use of the relatively short spatial wavelength behavior of the static effect in an analogous fashion to Bostick's method and tuning the data to the desired exploration objective; and (3) a linear correction is made to the model parameters. This three-step sequence is repeated, possibly varying the model definition or processing as interpretive judgement dictates, until the quality of fit of synthetic and field data is less than the typical data uncertainty. These data can be processed to remove shallow effects while maintaining the deep penetration characteristics of the natural electromagnetic (EM) field. Processing and modeling techniques for such data are demonstrated on both synthetic and field data. Very good agreement with actual borehole data is demonstrated

关键词： Bostick's method Oregon array response data acquisition deep penetration characteristics electric field geomagnetism geophysical prospecting geophysical techniques natural source electromagnetic array data numerically evaluated Jacobian shallow effects spatial wavelength behavior static removal terrestrial electricity three step sequence

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COMPUTER-AIDED-DESIGN OF array PATTERN

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ELECTRONICS LETTERS 1990年第25期26卷 2113-2115页

作者： ER, MH Sch. of Electr. & Electron. Eng. Nanyang Technol. Inst. Singapore

A computer-aided design technique for synthesising an antenna array pattern with an adjustable mainlobe width and minimum average sidelobe level is presented. The approach is based on a constrained optimisation problem designed to match the array response to a desired response over a mainlobe width while minimising the mean-square value of the array response over the sidelobe regions. Numerical results are presented to illustrate the performance achievable.

关键词： CAD antenna array pattern antenna arrays antenna radiation patterns array response computer-aided design technique constrained optimisation problem mainlobe width mean-square value minimum average sidelobe level numerical analysis numerical results optimisation sidelobe regions telecommunications computing

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array SYNTHESIS USING A SIMPLE COMPUTER-AIDED APPROACH

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ELECTRONICS LETTERS 1990年第5期26卷 337-339页

作者： NG, BP Dept. of Singapore Polytech. Electron. & Commun. Eng. Singapore

A simple computer-aided approach is used to design the beampattern of an array of arbitrary geometrical shape with minimum white noise output power. The basic idea of the approach is to minimise the mean-square value of the array response in certain directional regions while imposing a directional gain constraint at one frequency or over a frequency band of interest.

关键词： CAD CAD antenna array synthesis antenna arrays antenna radiation patterns antenna theory arbitrary geometrical shape array array response beampattern design computer-aided approach directional gain constraint directional regions frequency band mean-square value telecommunications computing white noise output power

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Communication and Localization With Extremely Large Lens Antenna array

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2021年第5期20卷 3031-3048页

作者： Yang, Jie Zeng, Yong Jin, Shi Wen, Chao-Kai Xu, Pingping Southeast Univ Natl Mobile Commun Res Lab Nanjing 210096 Peoples R China Natl Sun Yat Sen Univ Inst Commun Engn Kaohsiung 804 Taiwan

Achieving high-rate communication with accurate localization and wireless environment sensing has emerged as an important trend of beyond-fifth and sixth generation cellular systems. Extension of the antenna array to an extremely large scale is a potential technology for achieving such goals. However, the super massive operating antennas significantly increases the computational complexity of the system. Motivated by the inherent advantages of lens antenna arrays in reducing system complexity, we consider communication and localization problems with an extremely large lens antenna array, which we call "ExLens". Since radiative near-field property emerges in the setting, we derive the closed-form array response of the lens antenna array with spherical wave, which includes the array response obtained on the basis of uniform plane wave as a special case. Our derivation result reveals a window effect for energy focusing property of ExLens, which indicates that ExLens has great potential in position sensing and multi-user communication. We also propose an effective method for location and channel parameters estimation, which is able to achieve the localization performance close to the Cramer-Rao lower bound. Finally, we examine the multi-user communication performance of ExLens that serves coexisting near-field and far-field users. Numerical results demonstrate the effectiveness of the proposed channel estimation method and show that ExLens with a minimum mean square error receiver achieves significant spectral efficiency gains and complexity-and-cost reductions compared with a uniform linear array.

关键词： array response extremely large lens antenna array localization millimeter-wave communications spherical wave-front

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