Research Of DOA Estimation Algorithm In An Impulsive Noise Environment

The estimation of direction-of-arrival (DOA) is an important area in array signalprocessing. The methods based on array signal processing can estimate DOA of severalsources in different directions simultaneously. In conventional array signal processing，people used to describe interference or noise with Gaussian distribution model and analysisand deal with them based on second-order statistics, this is feasible in most cases. In manypractical applications, many random signals and noise that we encountered are not Gaussiandistributed, such as atmospheric noise, underwater acoustic signals, artificial signals and soon. And they are sudden impulsive phenomenons. Recent studies show that the rationalmodel of impulsive noise is SαS process. So the study of direction finding algorithms underthe environment of the impulsive noise has great significance.This paper is divided into two main tasks. As for the DOA estimation approaches ofuniform circular array and coherent sources in an impulsive noise environment, this paper isbased on the idea of the mode space transformation algorithm and the spatial smoothingalgorithm, the technology of pretreatment is also be used, the uniform circular array in thearray element space is transformed into the virtual uniform linear array in the phase modespace. So the DOA of uniform circular array and coherent sources in an impulsive noiseenvironment can be estimated using ROC-MUSIC algorithm and FLOM-MUSIC algorithmcombined the feature of the impulsive noise environment. As for the problems of DOAestimation of arbitrary array in an impulsive noise environment, this method of virtual arraytransformation is used. Arbitrary array is converted to uniform linear array so that its arrayflow has the Vandermonde form, and then the DOA of arbitrary array is estimatedeffectively using ROC-MUSIC algorithm and FLOM-MUSIC algorithm.