Method and apparatus for associating target replies with target signatures
First Claim
1. A method for associating target reply signals with target signatures, wherein each reply signal is received from a target transponder within a selectable time period, and further wherein each target signature comprises a first set of parameter values that identify a target position and movement relative to an interrogating aircraft, comprising the steps of:
- a. producing a target report for each reply signal, each said target report comprising a second set of parameter values;
b. comparing each target report with each target signature to identify which report/signature pairs are potential matches, each comparison between a target report and a target signature being based on comparisons of corresponding parameter values;
c. assigning a probability of match (Pm) for each report/signature potential match based on probability of match for each of said compared parameters;
d. assigning a probability of correct correlation (Pcc) for each report/signature potential match based on a comparison of Pm values of all said potential matches; and
e. identifying ambiguous report/signature matches based on comparison of said Pcc values of all said potential matches and a best report/signature match from said identified ambiguous matches based on a comparison of said parameters'"'"' probabilities of match thereof.
7 Assignments
0 Petitions
Accused Products
Abstract
Apparatus for associating target reply signals with target signatures, wherein each reply signal is received from a target transponder within a selectable time period, and further wherein each target signature comprises a first set of parameter values that identify a target position and movement relative to an interrogating aircraft, the apparatus including reply processor means for producing a target report for each reply signal, the target report having a second set of parameter values; and report processing means for: 1) comparing each target report with each target signature to identify which report/signature pairs are potential matches, each comparison between a target report and a target signature being based on comparisons of corresponding parameter values to produce a probability of match for each parameter comparison; and 2) identifying which report/signature matches are best based on comparison of each report/signature potential match with each other potential report/signature potential match including comparison of the parameters'"'"' probabilities of match. An improved method for compensating inaccurate bearing data is also provided.
63 Citations
25 Claims
-
1. A method for associating target reply signals with target signatures, wherein each reply signal is received from a target transponder within a selectable time period, and further wherein each target signature comprises a first set of parameter values that identify a target position and movement relative to an interrogating aircraft, comprising the steps of:
-
a. producing a target report for each reply signal, each said target report comprising a second set of parameter values; b. comparing each target report with each target signature to identify which report/signature pairs are potential matches, each comparison between a target report and a target signature being based on comparisons of corresponding parameter values; c. assigning a probability of match (Pm) for each report/signature potential match based on probability of match for each of said compared parameters; d. assigning a probability of correct correlation (Pcc) for each report/signature potential match based on a comparison of Pm values of all said potential matches; and e. identifying ambiguous report/signature matches based on comparison of said Pcc values of all said potential matches and a best report/signature match from said identified ambiguous matches based on a comparison of said parameters'"'"' probabilities of match thereof. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. Apparatus for associating target reply signals with target signatures, wherein each reply signal is received from a target transponder within a selectable time period, and further wherein each target signature comprises a first set of parameter values that identify a target position and movement relative to an interrogating aircraft, comprising:
-
antenna means for receiving the reply signals and producing phase related signals corresponding to target bearing and video signals corresponding to range based on a differential time of arrival (DTA) value relative to said time period; means for determining an altitude code associated with each reply signal; and processing means for;
1) producing, for each reply signal, a target report comprising a second set of parameters that includes at least a DTA value and may include altitude and bearing data when available from the reply signal;
2) comparing each target report with each of the target signatures to identify which report/signature pairs are potential matches, each comparison between a target report and a target signature being based on comparisons of corresponding parameter values to provide a probability of match for each parameter comparison; and
3) determining which target reports best match respective target signatures based on a comparison of each report/signature potential match with each other potential report/signature potential match including comparison of said parameters'"'"' probabilities of match. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22)
-
-
23. A method for associating target reply signals with target signatures, wherein each reply signal is received from a target transponder within a selectable time period, and further wherein each target signature comprises a first set of parameter values that identify a target position and movement relative to an interrogating aircraft, comprising the steps of:
-
a. producing a target report for each reply signal, said target report comprising a second set of parameter values; b. comparing each target report with each target signature to identify which report/signature pairs are potential matches, each comparison between a target report and a target signature being based on comparisons of corresponding parameter values to produce a probability of match for each parameter comparison; and c. identifying ambiguous report/signature matches based on comparison of each report/signature potential match with each other potential report/signature potential match and a best report/signature match from said identified ambiguous matches based on a comparison of said parameters'"'"' probabilities of match thereof.
-
-
24. Apparatus for associating target reply signals with target signatures, wherein each reply signal is received from a target transponder within a selectable time period, and further wherein each target signature comprises a first set of parameter values that identify a target position and movement relative to an interrogating aircraft, comprising:
-
reply processor means for producing a target report for each reply signal, said target report comprising a second set of parameter values; and report processing means for;
1) comparing each target report with each target signature to identify which report/signature pairs are potential matches, each comparison between a target report and a target signature being based on comparisons of corresponding parameter values to produce corresponding probability of match for each parameter comparison; and
2) identifying ambiguous report/signature matches based on comparison of each report/signature potential match with each other potential report/signature potential match and a best report/signature match from said identified ambiguous matches based on a comparison of said parameters'"'"' probabilities of match thereof.
-
-
25. A method for improving target track initiation comprising the steps of:
-
a. using a directional antenna to detect reply signals transmitted from a target during discrete time periods; b. determining a target bearing value for each of said detected reply signals; c. computing a bearing velocity (v.sub.θ
) based on bearing rate of change during said time periods; andd. attenuating said bearing velocity in relation to range of the target.
-
Specification