Spatially Spread Dipole/Loop Quads/Quints: For Direction Finding and Polarization Estimation

This letter shows how the four/five spatially noncollocated dipoles/loops by themselves suffice for multisource azimuth/elevation direction finding and polarization estimation. The mutual coupling across the antennas is reduced, and the array-aperture is extended to enhance the direction-of-arrival estimation accuracy since the intersensor spacings are far larger than a half-wavelength. The Cramér-Rao bounds are also derived to evaluate the performance of the proposed array schemes.