EXTRACTION OF RELATIVE SIGNALS FROM CLOSELY SPACED TARGETS IN A MONOPULSE SYSTEM
First Claim
1. A method for extracting at least one relative signal parameter representing two closely spaced targets from monopulse scan data, comprising a quadrature angle value and a merged azimuth angle value for each plurality of boresight angles, from a monopulse scanner comprising:
- comparing a maximum quadrature angle value from the quadrature angle values associated with the plurality of boresight angles with a threshold quadrature value representing a noise level of the monopulse scan data;
extracting the at least one relative signal parameter according to a cubic polynomial model that is configured to fit the merged azimuth angle values to a cubic function of their corresponding boresight angles to produce a set of polynomial coefficients and determine the at least one relative signal parameter from the set of polynomial coefficients if the maximum quadrature angle fails to exceed the threshold quadrature value; and
extracting the at least one relative signal parameter according to a linear polynomial model that is configured to fit a function of the merged azimuth angle data associated with each boresight angle and the quadrature angle value associated with the boresight angle to a linear function of an exponential parameter that is an exponential function of the boresight angle to produce a first order coefficient and a constant value and determine the at least one relative signal parameter from the first order coefficient and the constant value if the maximum quadrature angle exceeds the threshold quadrature value.
2 Assignments
0 Petitions
Accused Products
Abstract
Systems and methods are provided for extracting relative signal parameters representing two closely spaced targets from monopulse scan data. A maximum quadrature angle value from the scan data is compared with a threshold quadrature value representing a noise level. A linear polynomial model is utilized if the maximum quadrature angle exceeds the threshold value. The linear polynomial model fits a function of the azimuth angle values and quadrature angle values to a linear function of an exponential parameter derived from the boresight angles to produce polynomial coefficients and determines the relative signal parameters from the polynomial coefficients. A cubic polynomial model is utilized if the maximum quadrature angle fails to exceed the threshold value. The cubic polynomial model fits azimuth angle values to a cubic function of corresponding boresight angles to produce a set of polynomial coefficients and determines the relative signal parameters from the set of polynomial coefficients.
-
Citations
20 Claims
-
1. A method for extracting at least one relative signal parameter representing two closely spaced targets from monopulse scan data, comprising a quadrature angle value and a merged azimuth angle value for each plurality of boresight angles, from a monopulse scanner comprising:
-
comparing a maximum quadrature angle value from the quadrature angle values associated with the plurality of boresight angles with a threshold quadrature value representing a noise level of the monopulse scan data; extracting the at least one relative signal parameter according to a cubic polynomial model that is configured to fit the merged azimuth angle values to a cubic function of their corresponding boresight angles to produce a set of polynomial coefficients and determine the at least one relative signal parameter from the set of polynomial coefficients if the maximum quadrature angle fails to exceed the threshold quadrature value; and extracting the at least one relative signal parameter according to a linear polynomial model that is configured to fit a function of the merged azimuth angle data associated with each boresight angle and the quadrature angle value associated with the boresight angle to a linear function of an exponential parameter that is an exponential function of the boresight angle to produce a first order coefficient and a constant value and determine the at least one relative signal parameter from the first order coefficient and the constant value if the maximum quadrature angle exceeds the threshold quadrature value. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A system for extracting at least one relative signal parameter representing two closely spaced targets from monopulse scan data, comprising a quadrature angle value and a merged azimuth angle value for each plurality of boresight angles, from a monopulse scanner comprising:
-
an exponential parameter generator configured to calculate, for each antenna boresight angle, an exponential parameter that is an exponential function of the boresight angle; a modified ratio generator configured to compute, for each boresight angle, a modified ratio value as a function of the merged azimuth angle data associated with the boresight angle and the quadrature angle value associated with the boresight angle; a linear regression component configured to fit the modified ratio values for the plurality of boresight angles to a linear function of the exponential parameters for the plurality of boresight angles via a linear regression analysis to provide a first order coefficient value and a constant value; and a relative signal determination component configured to calculate at least one relative signal parameter representing the two closely spaced targets as a function of the first order coefficient value and the constant value. - View Dependent Claims (7, 8, 9, 10, 11, 12, 13)
-
-
14. A system for extracting at least one relative signal parameter representing two closely spaced targets from monopulse scan data, comprising a quadrature angle value and a merged azimuth angle value for each plurality of boresight angles, from a monopulse scanner comprising:
-
a multilinear regression element configured to fit the merged azimuth angle values to a cubic function of their corresponding boresight angles to produce a set of polynomial coefficients; an azimuth angle calculator configured to determine an azimuth difference as a difference between a first azimuth angle value for a first target and a second azimuth angle value for a second target and an azimuth mean as a mean of the first azimuth angle value and a second azimuth angle value from the set of polynomial coefficients; and a relative signal determination element configured to calculate at least one relative signal parameter representing the two closely spaced targets as a function of the azimuth difference, the azimuth mean, and the set of polynomial coefficients. - View Dependent Claims (15, 16, 17, 18, 19, 20)
-
Specification