An adaptive beamformer that is robust to uncertainty in source direction-of-arrival (DOA) is derived using a Bayesian approach. The DOA is assumed to be a discrete random variable with a known a priori probability density function (pdf) that reflects the level of uncertainty in the source DOA. The resulting beamformer is a weighted sum of minimum variance distortionless response (MVDR) beamform...

In this paper, ‘T’ character-type array antenna system is proposed which estimates the directions of arrival (DOA) by the virtual uniform rectangular arrays. The proposed system consists of 4 antenna elements distributed like the character ‘T’. The performance of the proposed system in DOA estimation is evaluated by some simulation and experiments. First we show that DOA is estimated correctly ...

This paper addresses the problem of direction-of-arrival (DOA) estimation of correlated and coherent signals, and two sparsityinducing methods are proposed. In the first method named L1-EVD, the signal-subspace eigenvectors are represented jointly with wellchosen hard thresholds attached to the representation residue of each eigenvector. Then only the eigenvector corresponding to the largest ei...

In this paper, DOA estimation is an important research area in array signal processing. The performance of adaptive beamforming methods are known to degrade severly in the presence of uncertainty in the signal sight direction. We propose a novel adaptive beamforming with a Bayesian method. Bayesian method a posterior probability density DOA estimator has been shown to perform excellently. The p...

March 1, 2016 The directions of arrival (DOA) of plane waves are estimated from multi-snapshot sensor array data using Sparse Bayesian Learning (SBL). The prior source amplitudes is assumed independent zero-mean complex Gaussian distributed with hyperparameters the unknown variances (i.e. the source powers). For a complex Gaussian likelihood with hyperparameter the unknown noise variance, the c...

Two signal selective Unitary Cyclic DOA algorithms are presented by introducing a new forward-backward smoothed covariance matrix. Compared with conventional Cyclic DOA algorithms, the suggested approaches have better performance in the presence of multipath propagation. In addition, these approaches not only allow to select desired signals and to ignore interferences by exploiting the cyclosta...

In sensor array signal processing especially in Radar, there is a growing interest in the estimation of a targets direction of arrival (DOA) against strong background noise or interference. Many algorithms used to estimate target DOA broadly classified as classical beam forming techniques and subspace based techniques (high resolution algorithms).In this paper a new DOA estimator is proposed ba...

Pathogenic OPA1 mutations cause autosomal dominant optic atrophy (DOA), a condition characterized by the preferential loss of retinal ganglion cells and progressive optic nerve degeneration. Approximately 20% of affected patients will also develop more severe neuromuscular complications, an important disease subgroup known as DOA(+). Cytochrome c oxidase (COX)-negative fibres and multiple mitoc...

Preliminary studies suggest that maternal heat stress (HS) during late gestation exerts carryover effects on a calf's insulin response after weaning, but a comprehensive evaluation of how maternal HS affects calf intake, growth, and metabolic response from birth to weaning is lacking. Our objective was to evaluate the effects of maternal HS during the dry period on dry matter intake, growth, an...