Computational Aspects of Maximum Likelihood DOA Estimation of Two Targets with Applications to Automotive Radar

  • Philipp HeidenreichEmail author
  • Abdelhak M. Zoubir


Direction-of-arrival (DOA) estimation of two targets with a single snapshot plays an important role in many practically relevant scenarios in automotive radar for driver assistance systems. Conventional Fourier-based methods cannot resolve closely spaced targets, and high-resolution methods are required. Thus, we consider the maximum likelihood DOA estimator, which is applicable with a single snapshot. To reduce the computational burden, we propose a grid search procedure with a simplified objective function. The required projection operators are pre-calculated off-line and stored. To save storage space, we further propose a rotational shift of the field of view such that the relevant angular sector, which has to be evaluated, is centered with respect to the broadside. The final estimates are obtained using a quadratic interpolation. An example is presented to demonstrate the proposed method. Also, results obtained with experimental data from a typical application in automotive radar are shown.


Automotive radar Direction of arrival (DOA) Driver assistance systems Maximum likelihood (ML) estimation 


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© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.ADC Automotive Distance Control Systems GmbHLindauGermany
  2. 2.Signal Processing GroupTechnische Universität DarmstadtDarmstadtGermany

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