METHOD FOR ARRAY CALIBRATION IN HIGH-RESOLUTION SENSOR ARRAY-PROCESSING

With few exceptions, most high-resolution sensor array algorithms for direction of arrival (DOA) estimation are sensitive to the errors in t he nominal array manifold. Deviations from the true array manifold, ty pically resulting from mutual coupling, array channels mismatch and se nsor positioning errors, can seriously degrade the algorithms' perform ance. Several array calibration algorithms have been reported in the l iterature; however, only a handful have addressed the problem of calib rating the errors in the array manifold that result from the combined effects of mutual coupling, sensor positioning error and mismatch in t he array channels. This problem is addressed in the paper. By extendin g the array parametrisation to describe the deviations of the nominal array manifold from the actual array manifold, the array calibration p roblem considered can be posed as that of estimating the calibration m atrix and sensor positions. The array calibration method proposed esti mates the sensor positions and calibration matrix from a set of measur ed steering vectors. The usefulness and behaviour of the proposed cali bration method are illustrated through simulated experiments.