| J | Karimi H. R. & Manikas A. Manifold of a planar array and its effects on the accuracy of direction-finding systems IEE Proceedings - Radar, Sonar Navigation, Vol. 143, No. 6, pp. 349-357, December 1996. |
Abstract
The authors are concerned with the accuracy of azimuth and elevationestimates provided by a planar array of sensors and its relation tothe array manifold differential geometry. The paper builds on previouslypublished results regarding the influence of manifold differentialgeometry on the detection and resolution capabilities of linear arrays.The manifold of a planar array is introduced in terms of two families ofconstant-azimuth and constant-elevation curves, and their differentialgeometry is analysed as a function of array configuration. Circularapproximation is subsequently employed to derive novel expressions forthe Cramer-Rao lower bound on azimuth and elevation estimates in termsof the arc lengths and first curvatures of the respective constant-parameter manifold curves. The scenarios considered include the casesof a single emitter as well as that of two closely spaced uncorrelatedemitters of arbitrary powers. The results obtained are demonstrated forthe cases of two practical array configurations.