Publica
Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. On the estimation of grid offsets in CSbased directionofarrival estimation
: Ibrahim, Mohamed
 Institute of Electrical and Electronics Engineers IEEE; IEEE Signal Processing Society: IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP 2014. Vol.9 : Florence, Italy, 4  9 May 2014 Piscataway, NJ: IEEE, 2014 ISBN: 9781479928941 ISBN: 9781479928927 ISBN: 9781479928934 S.67766780 
 International Conference on Acoustics, Speech and Signal Processing (ICASSP) <39, 2014, Florence> 

 Englisch 
 Konferenzbeitrag 
 Fraunhofer IIS () 
 Richtungsschätzung (DoA); compressed sensing 
Abstract
Compressed Sensing (CS) has been recently applied to direction of arrival (DOA) estimation, leveraging the fact that a superposition of planar wavefronts corresponds to a sparse angular power spectrum. However, to apply the CS framework we need to construct a finite dictionary by sampling the angular domain with a predefined sampling grid. Therefore, the target locations are almost surely not located exactly on a subset of these grid points. This leads to a model mismatch which deteriorates the performance of the estimators. In this paper we take an analytical approach to investigate the effect of such grid offsets on the recovered spectra. We show that each offgrid source can be well approximated by the closest two neighboring points on the grid. We propose a simple and efficient scheme to estimate the grid offset for a single source or multiple wellseparated sources. We also discuss a numerical procedure for the joint estimation of the grid offsets of closer sources. Simulation results demonstrate the effectiveness of the proposed methods.