Locating an object of interest using back tracked-rays derived from multipath signals
First Claim
1. A method for locating an object of interest, the method comprising:
- a) accepting at an observation point, signals emanating from the object;
b) determining, for each of the accepted signals, a direction of arrival;
c) determining at least two trace-back rays from the observation point using solely the direction of arrival of signals and topographical information;
d) determining at least one candidate location at crossings of two or more trace-back rays;
e) determining a set of final candidate locations from the determined candidate locations; and
f) determining the location of the object of interest using the set of final candidate locations, wherein the act of determining the location of the object of interest using the set of final candidate locations includesi) defining an area of accuracy including at least one candidate location from the set of final candidate locations, andii) determining the location of the object of interest using the defined area of accuracy,wherein at least two areas of accuracy are defined, andwherein the act of determining the location of the object of interest uses a cardinality of each of the areas of accuracy.
3 Assignments
0 Petitions
Accused Products
Abstract
Multipath signals (rays) emanating from an object of interest are processed to locate the object. Multipath signals may be accepted, screened, and associated with a specific object by an observer. Information (time, amplitude, and angle information) may be recorded for each ray. A set of incoming rays associated with a signal from an object are traced back toward the emanating object generating traceback ray segments. Candidate crossings of ray traceback segments are tested for time and/or amplitude consistency with ray information, and candidate crossings with inconsistent amplitude and/or time information may be eliminated from consideration. If there is only one candidate crossing remaining, it may be used to define the object location. Otherwise, the remaining crossings may be grouped, each grouping with a crossing cardinality, and location. Multiple crossings of multiple rays may be grouped into clusters with a cluster cardinality and diameter. The location may then be determined using crossing cardinality, cluster cardinality, and/or cluster diameter.
-
Citations
42 Claims
-
1. A method for locating an object of interest, the method comprising:
-
a) accepting at an observation point, signals emanating from the object; b) determining, for each of the accepted signals, a direction of arrival; c) determining at least two trace-back rays from the observation point using solely the direction of arrival of signals and topographical information; d) determining at least one candidate location at crossings of two or more trace-back rays; e) determining a set of final candidate locations from the determined candidate locations; and f) determining the location of the object of interest using the set of final candidate locations, wherein the act of determining the location of the object of interest using the set of final candidate locations includes i) defining an area of accuracy including at least one candidate location from the set of final candidate locations, and ii) determining the location of the object of interest using the defined area of accuracy, wherein at least two areas of accuracy are defined, and wherein the act of determining the location of the object of interest uses a cardinality of each of the areas of accuracy. - View Dependent Claims (2)
-
-
3. A method for locating an object of interest, the method comprising:
-
a) accepting at an observation point, signals emanating from the object; b) determining, for each of the accepted signals, a direction of arrival; c) determining at least two trace-back rays from the observation point using solely the direction of arrival of signals and topographical information; d) determining at least one candidate location at crossings of two or more trace-back rays; e) determining a set of final candidate locations from the determined candidate locations; and f) determining the location of the object of interest using the set of final candidate locations, wherein the act of determining the location of the object of interest using the set of final candidate locations includes i) defining an area of accuracy including at least one candidate location from the set of final candidate locations, and ii) determining the location of the object of interest using the defined area of accuracy, wherein at least two areas of accuracy are defined, and wherein the act of determining the location of the object of interest includes A) defining at least one cluster, each cluster including locations of each of at least two areas of accuracy, and B) determining the location of the object of interest using the at least one cluster. - View Dependent Claims (4, 5, 6, 7, 8)
-
-
9. A method for locating an object of interest, the method comprising:
-
a) accepting at an observation point, signals emanating from the object; b) determining, for each of the accepted signals, a direction of arrival; c) determining at least two trace-back rays from the observation point using solely the direction of arrival of signals and topographical information; d) determining at least one candidate location at crossings of two or more trace-back rays; e) determining a set of final candidate locations from the determined candidate locations; and f) determining the location of the object of interest using the set of final candidate locations, wherein the act of determining the location of the object of interest using the set of final candidate locations includes i) defining a volume of accuracy including at least one candidate location from the set of final candidate locations, and ii) determining the location of the object of interest using the defined volume of accuracy. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39)
-
-
40. Apparatus for locating an object of interest, the apparatus comprising:
-
a) means for accepting at an observation point, signals emanating from the object; b) means for determining, for each of the accepted signals, a direction of arrival; c) means for determining at least two trace-back rays from the observation point using solely the direction of arrival of signals and topographical information; d) means for determining at least one candidate location at crossings of two or more trace-back rays; e) means for determining a set of final candidate locations from the determined candidate locations; and f) means for determining the location of the object of interest using the set of final candidate locations, wherein the means for determining the location of the object of interest using the set of final candidate locations include i) means for defining an area of accuracy including at least one candidate location from the set of final candidate locations, and ii) means for determining the location of the object of interest using the defined area of accuracy, wherein at least two areas of accuracy are defined, and wherein the means for determining the location of the object of interest use a cardinality of each of the areas of accuracy.
-
-
41. Apparatus for locating an object of interest, the apparatus comprising:
-
a) means for accepting at an observation point, signals emanating from the object; b) means for determining, for each of the accepted signals, a direction of arrival; c) means for determining at least two trace-back rays from the observation point using solely the direction of arrival of signals and topographical information; d) means for determining at least one candidate location at crossings of two or more trace-back rays; e) means for determining a set of final candidate locations from the determined candidate locations; and f) means for determining the location of the object of interest using the set of final candidate locations, wherein the means for determining the location of the object of interest using the set of final candidate locations include i) means for defining an area of accuracy including at least one candidate location from the set of final candidate locations, and ii) means for determining the location of the object of interest using the defined area of accuracy, wherein at least two areas of accuracy are defined, and wherein the means for determining the location of the object of interest include A) means for defining at least one cluster, each cluster including locations of each of at least two areas of accuracy, and B) means for determining the location of the object of interest using the at least one cluster.
-
-
42. Apparatus for locating an object of interest, the apparatus comprising:
-
a) means for accepting at an observation point, signals emanating from the object; b) means for determining, for each of the accepted signals, a direction of arrival; c) means for determining at least two trace-back rays from the observation point using solely the direction of arrival of signals and topographical information; d) means for determining at least one candidate location at crossings of two or more trace-back rays; e) means for determining a set of final candidate locations from the determined candidate locations; and f) means for determining the location of the object of interest using the set of final candidate locations, wherein the means for determining the location of the object of interest using the set of final candidate locations include i) means for defining a volume of accuracy including at least one candidate location from the set of final candidate locations, and ii) means for determining the location of the object of interest using the defined volume of accuracy.
-
Specification