Tracking system

• US 5,285,273 A
• Filed: 02/19/1988
• Issued: 02/08/1994
• Est. Priority Date: 02/19/1987
• Status: Expired due to Fees

• Current Assignee: Matra Bae Dynamics
• Original Assignee: British Aerospace, Inc.
• Inventors: Stafford, Raymond J. P., James, Enoch
• Primary Examiner(s): Buczinski, Stephen C.
• Application Number:
  US07/167,480
• Time in Patent Office: 2,181 Days
• Field of Search: 358/125, 358/126, 250/203 CT, 250/203.5, 89/41.05, 89/41.06, 382/45, 382/47
• US Class Current: 348/169
• CPC Class Codes: F41G 7/2226 comparing the observed data with stored target data, e.g. target configuration data
• CPC Class Codes: F41G 7/2253 Passive homing systems, i.e. comprising a receiver and do not requiring an active illumination of the target
• CPC Class Codes: F41G 7/2293 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 3/7865 using correlation of the live video image with a stored image
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 7/248 involving reference images or patches

Abstract

An automatic target tracking system comprising video means, target tracking means, correlation means and aimpoint location means which predicts the subsequent position of a target after each viewing by the video means and then correlates this with the actual viewing of the target position so as to estimate that position within a given field of view.

Claims

1. An automatic target tracking system comprising:

imaging means for forming a video signal representative of successive images of a viewed scene;

target tracking means, coupled to the imaging means, for locating a target within one of said images and for predicting the likely position of said target within a subsequent image;

correlation means for correlating features of said one of said images with a previous one of said images;

image decomposition means for selecting the correlating features which relate to the target, and for enhancing these features; and

aim point location means for determining an aimpoint for the target by analysis of the enhanced correlating features and for updating the target position predicted by the target tracking means.

2. A method of automatically tracking a target utilizing a sensor means for supplying a video signal indicative of a viewed scene, and a computer means including a memory, said computer including the operating steps of:

recording data indicative of the locations of a target within said scene during formation of a plurality of successive video signal fields and using said data to predict the target location during formation of a subsequent video signal field;

memorizing at least part of a previously received video signal field representative of a portion of the viewed scene containing said target;

using said predicted target location to identify a search area, within said scene, expected to contain said target during formation of said subsequent video signal field;

correlating said memorized previously received video signal part against at least a part of said subsequent video signal field representative of said search area in order to identify the actual location of said target during formation of this subsequent video signal field, and to produce a correlation signal indicative of features in the video signal;

decomposing the correlation signal to identify and enhance target features present in the correlation signal;

determining an aimpoint by analyzing the target features; and

using the aimpoint to further update the prediction of the target location during formation of the subsequent video signal field.

3. An automatic target tracking system comprising sensor means for supplying a video signal indicative of a viewed scene, and a computer means, said computer means including:

means for recording data indicative of the locations of a target within said scene during formation of a plurality of successive video signal fields and for using said data to predict the target location during formation of a subsequent video signal field;

means for memorizing at least part of a previously received video signal field representative of a portion of the viewed scene containing said target;

means for using said predicted target location to identify a search area, within said scene, expected to contain said target during formation of said subsequent video signal field;

means for correlating said memorized previously received video signal part against at least a part of said subsequent video signal field representative of said search area in order to identify the actual location of said target during formation of this subsequent video signal field, and to produce a correlation signal indicative of features in the video signal;

means for decomposing the correlation signal to identify and enhance target features present in the correlation signal;

means for determining an aimpoint by analyzing the target features; and

means for using the aimpoint to further update the prediction of the target location during formation of the subsequent video signal field.