Paper Info
Title
A general superdirectivity model for arbitrary sensor arrays
Abstract
This paper proposes a general model of superdirectivity to provide analytical and closed-form solutions for arbitrary sensor arrays. Based on the equivalence between the maximum directivity factor and the maximum array gain in the isotropic noise field, Gram-Schmidt orthogonalization is introduced and recursively transformed into a matrix form to conduct pre-whitening and matching operations that result in superdirectivity solutions. A Gram-Schmidt mode-beam decomposition and synthesis method is then presented to formally implement these solutions. Illustrative examples for different arrays are provided to demonstrate the feasibility of this method, and a reduced rank technique is used to deal with the practical array design for robust beamforming and acceptable high-order superdirectivity. Experimental results that are provided for a linear array consisting of nine hydrophones show the good performance of the technique. A superdirective beampattern with a beamwidth of 48.05° in the endfire direction is typically achieved when the inter-sensor spacing is only 0.09λ (λ is the wavelength), and the directivity index is up to 12 dB, which outperforms that of the conventional delay-and-sum counterpart by 6 dB.
Year
DOI
Venue
2015
10.1186/s13634-015-0250-x
EURASIP Journal on Advances in Signal Processing
Keywords
Field
DocType
Gram-Schmidt orthogonalization, High-order superdirectivity, Mode-beam decomposition and synthesis, Optimal beamforming, Sonar signal processing
Isotropy,Gram–Schmidt process,Computer science,Artificial intelligence,Array gain,Beamwidth,Computer vision,Beamforming,Directivity,Algorithm,Orthogonalization,Electrical engineering,Sonar signal processing
Journal
Volume
Issue
ISSN
2015
1
1687-6180
Citations 
PageRank 
References 
2
0.41
8
Authors
5
Name
Order
Citations
PageRank
Yong Wang142.81
Yixin Yang23311.80
Zhengyao He320.75
Yina Han420.41
Y Ma513015.55