Abstract: Data compression method, system, and program code for compressing antenna pattern data generated by measuring the complex voltage derived from the interaction of a RF waveform and a sensing element are disclosed. The antenna pattern data are modeled with a plurality of infinitesimal antenna elements, each element defined in terms of a distinct position, orientation, and polarization. An analytical expression for the interaction between the plurality of infinitesimal antenna elements and an impinging waveform yields a plurality of expressions for a theoretical voltage. The plurality of infinitesimal antenna elements constitute a mathematical basis set from which a weighted linear combination is constructed. The value of the weights are determined by equating the complex voltage representing the antenna pattern data with the theoretical voltage representing the plurality of weighted infinitesimal antenna elements.

Abstract: A carrier structure apparatus for mounting conformal antenna elements to a non-planar mounting surface as part of an antenna array of an airborne vehicle or ground-based system also comprising a seeker section, fairing and guidance processing system. The carrier structure is a rigid and conductive apparatus that is made to conform to the geometric configuration of both the antenna element as well as the mounting surface. The conformal antenna is rigidly mounted to the carrier structure, which is in turn removably affixed to the non-planar mounting surface. With the carrier structure, each antenna element of the array may be individually tested and replaced prior to and after installation in array.

Abstract: A timing and control method and apparatus (111) for performing precise range rate aiding includes a range gate delay means (114) for generating an estimate of the range gate delay (135) each pulse repetition interval as a function of the initial range (134) and velocity (133) provided by a processor (104). The range gate delay (135) is converted into a coarse delay (138) defining the integral number of clock cycles preceding the range gate, and a fine delay (139) for positioning a range gate to within a fraction of a clock cycle. Fine temporal control is achieved using programmable delay lines (117) and (118), which retard various control signals, including the system clock signal (131), in accordance with the fine delay (139). A modified signal (126) then drives a counter means (119) which outputs a signal (128) that defines an analog-to-digital sampling window beginning at the elapse of the range gate delay (135).

Abstract: An apparatus and method for determining the angles-of-arrival and the polarization states of incoming RF signals of unknown polarization using five or more RF sensing antenna elements of differing yet known orientations of polarization.

Abstract: A method for resolving the angular ambiguity inherent in the differential phase measurements of a source of electromagnetic signal by an interferometric system of antenna elements. Three or more independent differential phase measurements are acquired between predetermined pairs of antenna elements. The ambiguous solutions to each of the differential phase measurements are represented as a group of equally-spaced, parallel lines. The points of intersection between two groups of lines represent ambiguous solutions to the system of equations from which the true angles-of-arrival may be determined. The set of ambiguous solutions is evaluated using the remaining differential phase measurements. The most probable solution to the system of equations is determined by minimizing cost functions with the following embodiments: tightest cluster of intersecting lines; maximum likelihood estimation; and voltage reconstruction comparisons with measured voltages.

Abstract: An apparatus and method for determining the angles-of-arrival and the polarization states of incoming RF signals of unknown polarization using three or more RF sensing antenna elements of differing yet known orientations of polarization.