3 research outputs found
Effective Acoustic Energy Sensing Exploitation for Target Sources Localization in Urban Acoustic Scenes
This letter proposes a new approach to improve the accuracy of the
Energy-based source localization methods in urban acoustic scenes. The proposed
acoustic energy sensing flow estimation (ESFE) uses the sensors signal
nonstationarity degree to determine the area with highest energy concentration
in the scenes. The ESFE is applied to different acoustic scenes and yields to
source localization accuracy improvement with computational complexity
reduction. The experiments results show that the proposed scheme leads to
significant improvement in source localization accuracy
Hybrid Sparse Array Beamforming Design for General Rank Signal Models
The paper considers sparse array design for receive beamforming achieving
maximum signal-to-interference plus noise ratio (MaxSINR) for both single point
source and multiple point sources, operating in an interference active
environment. Unlike existing sparse design methods which either deal with
structured environment-independent or non-structured environment-dependent
arrays, our method is a hybrid approach and seeks a full augumentable array
that optimizes beamformer performance. This approach proves important for
limited aperture that constrains the number of possible uniform grid points for
sensor placements. The problem is formulated as quadratically constraint
quadratic program (QCQP), with the cost function penalized with weighted
l_1-norm squared of the beamformer weight vector. Simulation results are
presented to show the effectiveness of the proposed algorithms for array
configurability in the case of both single and general rank signal correlation
matrices. Performance comparisons among the proposed sparse array, the commonly
used uniform arrays, arrays obtained by other design methods, and arrays
designed without the augmentability constraint are provided
Sparse Array Beamformer Design for Active and Passive Sensing
Sparse sensor placement, with various design objectives, has successfully
been employed in diverse application areas, particularly for enhanced parameter
estimation and receiver performance. The sparse array design criteria are
generally categorized into environment-independent and environment-dependent
performance metrics. The former are largely benign to the underlying
environment and, in principle, seek to maximize the spatial degrees of freedom
by extending the coarray aperture. Environment-dependent objectives, on the
other hand, consider the operating conditions characterized by emitters and
targets in the array field of view, in addition to receiver noise. In this
regard, applying such objectives renders the array configuration as well as the
array weights time-varying in response to dynamic and changing environment.
This work is geared towards designing environment-dependent sparse array
beamformer to improve the output signal-to-interference and noise ratio using
both narrowband and wideband signal platforms. One key challenge in
implementing the data-dependent approaches is the lack of knowledge of exact or
estimated values of the data autocorrelation function across the full sparse
array aperture. At the core of this work is to address the aforementioned
issues by devising innovative solutions using convex optimization and machine
learning tools, structured sparsity concepts, low rank matrix completion
schemes and fusing the environment-dependent and environment-independent deigns
by developing a hybrid approach.Comment: PhD thesi