Some Comparisons of Cram er Rao Bounds for Vector Sensors and Scalar Sensor Arrays for Array Processing

The e ect from polarization of emitted wave fronts on the parameter estimation ac curacy for an array composed only of sensors sensitive to just one polarization direction has not been addressed in the literature this far Antennas with such characteristics are e g dipole or scalar antennas A vector sensor on the other hand is a sen sor whose output data consists of for the electromagnetic case the complete electric and magnetic elds at the sensor This paper examines some of the e ects on the Cram er Rao Bound for the elevation and or azimuth angles to a single source emit ting a polarized electromagnetic waveform Since only one vector sensor is needed for estimation of both azimuth and elevation it would be of interest to compare the lower parameter estimation error bound resulting from the vector sensor data model to the ordinary one i e the data model used for scalar arrays Such comparisons both analytically and numerically are herein made for an acoustic data model as well as for an electromagnetic measurement model for some simple scenarios and array con gurations The work of A Nehorai was supported by the Air Force O ce of Scienti c Research under Grant no F the O ce of Naval Research under Grant no N J and the National Science Foundation under Grant no MIP On leave from the Department of Electrical Engineering Link oping University S Link oping Sweden