EXPERIMENTAL EVALUATION OF HIGH-RESOLUTION DIRECTION-FINDING ALGORITHMS USING A CALIBRATED SENSOR ARRAY TESTBED

In this paper the performance of several direction-finding algorithms is investigated experimentally using the University of Minnesota Senso r Array Testbed. In recent years, many ''high-resolution'' direction-f inding algorithms have been investigated using computer simulation and theoretical analysis. For the most part, no systematic experimental e valuation of these algorithms has been reported in the open literature . An experimental array testbed allows further evaluation of the capab ilities and limitations of these algorithms. The system at the Univers ity of Minnesota basically consists of a linear array of eight ultraso nic transducers and several transmitters operating at 40 kHz in air. N onideal conditions in actual arrays require calibration, and the metho ds of calibrating the sensor array testbed are described. Experimental results are presented, which compare the performance of several well- known algorithms, including Capon's MLM, MUSIC, Root-MUSIC, Min-Norm, ESPRIT, and a weighted norm version of MUSIC. The analysis includes ex perimental resolution thresholds, estimate bias and variance calculati ons, and comparisons with simulated results and the Cramer-Rao lower b ound for variance. (C) 1995 Academic Press, Inc.