System for automatic initiation of target tracking in track-while-scan radar

Claim 2

In a multi-target track-while-scan radar system including a memory for storing a track representing the predicted position of a target being tracked at a selected time, means for producing a sequence of input plots representing the position of an object, and means for correlating the track in said memory and said input plot, the improvement comprising: said memory storing said track in range and azimuth parameters; said means for producing an input plot providing said plots in range and azimuth parameters; a temporary memory having a predetermined capacity for storing plots; track initiation gating means for establishing a track initiation cOrrelation criteria; plot correlating means responsive to the absence of correlation between the track in said memory and each received input plot for serially correlating each received input plot with each plot stored in said temporary memory and providing signals when one of said stored plots correlates with said input plot, said signals being indicative of the position relationship of the two correlated plots; said plot correlating means also being responsive to the stored plot correlating with said input plot and said signals indicative of the position relationship therebetween for providing an initial target track representing the predicted position of a new target at a selected time; and means for storing said initial target track in said memory for correlation with a succeeding received input plot.

Claim 3

In a track-while-scan radar system for tracking a plurality of targets, the system including a video processor for processing video signals to provide input plots each representing the position of an object, a computer memory storing tracks of tracked targets, each track representing the predicted position of one of said targets, track correlator means for correlating said plot and each of said tracks in accordance with at least one selected correlation criteria, said track correlator further including means for providing position relationship signals which are functions of said input plot and the track with which it correlates, and tracking logic means responsive to said position relationship signals and track with which said plots correlated for providing an updated track representing a new predicted position of the target related to said correlated track, an improved system for automatically initiating the tracking of a target comprising: said video processor providing said plots represented by range signals and azimuth signals and said computer memory storing said track represented by range signals and azimuth signals; a temporary memory for storing at least one plot; track initiation gating means for defining an initiation correlation criteria; a plot correlator for initially correlating said input plot with said at least one plot in accordance with said initiation correlation criteria in the absence of correlation between said input plot and any of the tracks in said computer memory, said plot correlator including means coupled to said temporary memory for causing said input plot to be stored in said temporary memory in the absence of correlation therebetween and said at least one plot, said plot correlator providing signals indicative of the position relationship represented by said input plot and said at least one plot when the two correlate in said plot correlator in accordance with initiation correlation criteria, said tracking logic means being responsive to said signals and said at least one plot which correlates with said input plot for generating an initial track; and means coupling said tracking logic means and said computer memory for storing said initial track therein for correlation with a succeeding received input plot, said initial track representing the predicted position of a new target at a selected time from the time of arrival of said input plot.

Claim 4

In a track-while-scan radar system for tracking a plurality of targets, the system including a video processor for processing video signals to provide input plots each representing the position of an object, a computer memory storing tracks of tracked targets, each track representing the predicted position of one of said targets, track correlator means for correlating said plot and each of said tracks in accordance with at least one selected correlation criteria, said track correlator further including means for providing position relationship signals which are functions of said input plot and the track with which it correlates, and tracking logic means responsive to said position relationship signals and track with which said plots correlated for providing an updated track representing a new predicted position of the target related to said correlated track, an improved system for automatically initiating the tracking of a target comprising: said video processor providing said plots represented by range signals and azimuth signals and said computer memory storing said track represented by range signals and azimuth signals; a temporary memory for storing at least one plot; track initiation gating means for defining an initiation correlation criteria; a plot correlator for initially correlating said input plot with said at least one plot in accordance with said initiation correlation criteria in the absence of correlation between said input plot and any of the tracks in said computer memory, said plot correlator including means coupled to said temporary memory for causing said input plot to be stored in said temporary memory in the absence of correlation therebetween and said at least one plot, said plot correlator providing signals indicative of the position relationship represented by said input plot and said at least one plot when the two correlate in said plot correlator in accordance with initiation correlation criteria, said tracking logic means being responsive to said signals and said at least one plot which correlates with said input plot for generating an initial track; and means coupling said tracking logic means and said computer memory for storing said initial track therein for correlation with a succeeding received input plot, said initial track representing the predicted position of a new target at a selected time from the time of arrival of said input plot.

Claim 5

In the track-while-scan radar system recited in claim 2 further including means for generating said initiation correlation criteria as a function of the radar system''s root mean square error and the range of a target to be tracked.

Claim 6

In the track-while-scan radar system recited in claim 3 further including means in said means for storing for automatically rejecting said initial target track when said track does not correlate with any of the plots received during a predetermined time interval.

Claim 7

In the track-while-scan radar system recited in claim 4 wherein said predetermined time interval is greater than 2 times the scan time.

Claim 8

In the track-while-scan radar system recited in claim 4 further including means in said temporary memOry for erasing said stored plot from said memory when said stored plot does not correlate with an input plot during a predetermined time interval.

Claim 9

In the track-while-scan radar system recited in claim 6 wherein said time interval is greater than 2 times the scan time.

Claim 10

In the track-while-scan radar system recited in claim 3 wherein said plot correlator correlates the range signals of said input plot with the range signals of each plot stored in said temporary memory and provides a range difference signal when the difference between the range signals is not greater than a preselected range defined by said initiation correlation criteria, said plot correlator further correlates the azimuth signals of said input plot with the azimuth signals of each plot in said temporary memory to provide an azimuth difference signal when the difference between the azimuth signals is not greater than an azimuth value defined by said initiation correlation criteria, the range and azimuth difference signals from said plot correlator comprising the position relationship signals thereof.

Claim 11

In the track-while-scan radar system recited in claim 8 wherein said track initiation gating means includes means for providing the range and azimuth values defined by said initiation criteria as a function of the range and azimuth system''s root mean square errors respectively.

Claim 12

In the track-while-scan radar system recited in claim 2 wherein the range R signals and azimuth theta signals of each track and plot defining the position of a target with respect to a reference point and reference line respectively and wherein said track correlator includes means for correlating the range signals of said input plot with the range signals of each track in said computer memory for providing a range difference signal when the difference between the range signals is not greater than a preselected range value defined by said selected correlation criteria, said track correlator also being operative to correlate the azimuth signals of said input plot with the azimuth signals of each track in said computer memory, to provide an azimuth difference signal when the difference between the azimuth signals is not greater than an azimuth value defined by said selected correlation criteria, said range and azimuth difference signals comprising said position relationship signals provided by said track correlator.