Multiple and single snapshot compressive beamforming.

J Acoust Soc Am

Christian Doppler Lab, Institute of Telecommunications, TU Wien, Gusshausstrasse 25/389, 1040 Vienna, Austria.

Published: October 2015

For a sound field observed on a sensor array, compressive sensing (CS) reconstructs the direction of arrival (DOA) of multiple sources using a sparsity constraint. The DOA estimation is posed as an underdetermined problem by expressing the acoustic pressure at each sensor as a phase-lagged superposition of source amplitudes at all hypothetical DOAs. Regularizing with an ℓ1-norm constraint renders the problem solvable with convex optimization, and promoting sparsity gives high-resolution DOA maps. Here the sparse source distribution is derived using maximum a posteriori estimates for both single and multiple snapshots. CS does not require inversion of the data covariance matrix and thus works well even for a single snapshot where it gives higher resolution than conventional beamforming. For multiple snapshots, CS outperforms conventional high-resolution methods even with coherent arrivals and at low signal-to-noise ratio. The superior resolution of CS is demonstrated with vertical array data from the SWellEx96 experiment for coherent multi-paths.

Download full-text PDF

Source
http://dx.doi.org/10.1121/1.4929941DOI Listing

Publication Analysis

Top Keywords

single snapshot
8
multiple snapshots
8
multiple
4
multiple single
4
snapshot compressive
4
compressive beamforming
4
beamforming sound
4
sound field
4
field observed
4
observed sensor
4

Similar Publications

Trajectory inference from single-cell genomics data with a process time model.

PLoS Comput Biol

January 2025

Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, United States of America.

Single-cell transcriptomics experiments provide gene expression snapshots of heterogeneous cell populations across cell states. These snapshots have been used to infer trajectories and dynamic information even without intensive, time-series data by ordering cells according to gene expression similarity. However, while single-cell snapshots sometimes offer valuable insights into dynamic processes, current methods for ordering cells are limited by descriptive notions of "pseudotime" that lack intrinsic physical meaning.

View Article and Find Full Text PDF

Diffraction-before-destruction imaging with ultrashort X-ray pulses can visualize non-equilibrium processes, such as chemical reactions, with sub-femtosecond precision in the native environment. Here, a nanospecimen diffracts a single X-ray flash before it disintegrates. The sample structure can be reconstructed from the coherent diffraction image (CDI).

View Article and Find Full Text PDF

Background: Dolutegravir plus lamivudine has emerged as a preferred treatment for HIV; however, initiating this regimen without baseline resistance testing raises concerns about the potential presence of pretreatment lamivudine resistance. We aimed to evaluate the efficacy of dolutegravir plus lamivudine in the absence of information on baseline resistance testing in treatment-naive people with HIV.

Methods: We did an open-label, non-inferiority, single-centre, phase 4, randomised controlled study (D2ARLING), designed to assess the efficacy and safety of dolutegravir plus lamivudine in treatment-naive people with HIV with no available baseline resistance testing.

View Article and Find Full Text PDF

Evaluation of SNaPshot and Sanger sequencing for the detection of and mutations in a sample of Venezuelan patients with colorectal cancer.

Ecancermedicalscience

November 2024

Instituto Venezolano de Investigaciones Científicas (IVIC), Unidad de Estudios Genéticos y Forenses (UEGF), Caracas 1020, República Bolivariana de Venezuela.

Colorectal cancer (CRC) is the third most commonly occurring cancer in men and the second most commonly occurring cancer in women. The epidermal growth factor receptor (EGFR) is relevant in the development and progression of CRC, because it is part of multiple signaling pathways involved in processes of the cell cycle, their malfunction causes dysregulation and subsequently carcinogenesis. Consequently, therapies were developed with anti-EGFR monoclonal antibodies (MAbs) that improve the survival of patients with CRC.

View Article and Find Full Text PDF

Recent single-cell experiments that measure copy numbers of over 40 proteins in individual cells at different time points [time-stamped snapshot (TSS) data] exhibit cell-to-cell variability. Because the same cells cannot be tracked over time, TSS data provide key information about the time-evolution of protein abundances that could yield mechanisms that underlie signaling kinetics. We recently developed a generalized method of moments (GMM) based approach that estimates parameters of mechanistic models using TSS data.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!