Closed-loop infrared countermeasure system using high frame rate infrared receiver

Abstract

A missile tracking and deflection system for protecting a platform includes a missile warning system for detecting the presence of a missile and generating a warning signal. A countermeasure processor receives the warning signal and analyzes characteristics of the missile to prioritize a trajectory signal. A track processor receives the trajectory signal and generates a pointer signal. The system also includes a receiver, which is positioned by a pointer that receives the pointer signal, for receiving a passive and/or active signature of the missile to confirm the presence thereof. The countermeasure processor then directs a laser beam at the missile to determine its operational parameters and receives an active signature from the missile. The receiver delivers the passive and/or active signatures to the countermeasure processor and the track processor, wherein the track processor updates the pointer signal and the countermeasure processor generates a jam code delivered by the laser beam to divert the trajectory of the missile away from the platform.

What is claimed is:  
     
       1. A missile tracking and deflection system for protecting a platform, comprising: 
       a missile warning system for detecting the presence of a missile and generating a warning hand-off signal;  
       a countermeasure processor for receiving said warning hand-off signal and generating a trajectory signal;  
       a track processor for receiving said trajectory signal and generating a pointer trajectory signal;  
       a pointer for receiving said pointer trajectory signal to position said pointer toward the missile;  
       a laser positioned by said pointer, said laser emitting a laser beam at the missile to generate an active signature; and  
       an infrared receiver comprising an infrared focal plane array that integrally and simultaneously combines a tracking camera and a laser receiver, said infrared receiver positioned by said pointer, said camera receiving a passive signature of the missile and generating a trajectory characteristic signal received by said track processor for updating said pointer trajectory signal, said laser receiver receiving said active signature and generating a missile characteristic signal received by said countermeasure processor to identify the missile and generate a jam code carried by said laser beam to divert the trajectory of the missile away from the platform.  
     
     
       2. The system according to  claim 1 , wherein said focal plane array operates at least at a first and a second frame rate, said tracking camera operating at a first frame rate for tracking the missile over a large portion of said focal plane array to generate said trajectory characteristic signal which is received by said track processor for updating said trajectory pointer signal, said laser receiver operating at a second frame rate for observing the missile over a smaller portion of said focal plane array to receive said active signature. 
     
     
       3. The system according to  claim 2 , wherein said infrared receiver is bore-sighted with said laser, said laser receiving an initiation signal from said countermeasure processor to generate said laser beam, the missile returning said active signature to said laser receiver which receives said active signature and monitors the trajectory of the missile. 
     
     
       4. The system according to  claim 3 , wherein said focal plane array operates at a third frame rate over a mid-sized portion thereof, between said large portion and said small portion, said third frame rate establishing a high resolution tracking of the missile via said trajectory characteristic signal, wherein said countermeasure processor simultaneously monitors said trajectory characteristic signal and said active signature, and if needed, updates said jam code. 
     
     
       5. The system according to  claim 4 , wherein said first frame rate is about no greater than 120 frames per second. 
     
     
       6. The system according to  claim 4 , wherein said third frame rate is between about 120 to about 1000 frames per second and said mid-sized portion of said focal plane array is sized to be about 32×32 pixels. 
     
     
       7. The system according to  claim 4 , wherein said second frame rate is greater than about 1000 frames per second and said small portion of said focal plane array is sized to be about 16×16 pixels. 
     
     
       8. A method for diverting the trajectory of a missile, comprising the steps of: 
       detecting the presence of a missile and generating a warning hand-off signal;  
       analyzing characteristics of said warning handoff signal with a countermeasure processor which generates a trajectory signal;  
       processing said trajectory signal to generate a trajectory pointer signal;  
       receiving said pointer signal in a pointer that follows the missile trajectory, said pointer positioning a laser and an infrared receiver which has a single focal plane array that integrally and simultaneously combines the functions of a tracking camera and a laser receiver;  
       directing said laser to generate a laser beam toward the missile so as to generate an active signature;  
       observing said active signature with said laser receiver and observing a passive signature of the missile with said tracking camera to track the trajectory of the missile, said laser receiver observing said active signature to detect the operational characteristics of the missile, said infrared receiver delivering a signal to said countermeasure processor which generates a jam code employed to divert the trajectory of the missile.  
     
     
       9. The method according to  claim 8 , further comprising the steps of: 
       generating a missile characteristic signal by said laser receiver based upon said active signature; and  
       receiving said missile characteristic signal in said countermeasure processor which in turn generates said jam code for inclusion with said laser beam.  
     
     
       10. The method according to  claim 8 , further comprising the steps of: 
       generating a trajectory characteristic signal by said infrared receiver based upon said active signature or said passive signature; and  
       receiving said trajectory characteristic signal in a track processor which updates said trajectory signal.  
     
     
       11. The method according to  claim 8 , further comprising the step of: imaging said focal plane array at a rate of about no greater than 120 frames per second when initially receiving said pointer signal. 
     
     
       12. The method according to  claim 8 , further comprising the step of: 
       imaging said focal plane array at a rate between about 120 to about 1000 frames per second to establish a high resolution track on the missile.  
     
     
       13. The method according to  claim 8 , further comprising the step of: 
       imaging said focal plane array at a rate greater than about 1000 frames per second when said laser beam illuminates the missile and whereupon said jam code is included with said laser beam.  
     
     
       14. The method according to  claim 8 , further comprising the step of: 
       dispensing expendable countermeasure devices at the missile as instructed by said countermeasure processor.  
     
     
       15. An object tracking system comprising: 
       an infrared receiver for observing the object, said infrared receiver having a focal plane array for obtaining information about the object, said focal plane array integrally and simultaneously combining a tracking camera and a laser receiver;  
       a processor in communication with said infrared receiver, said processor controlling said focal plane array over at least two frame rates, wherein said tracking camera images a large portion of said focal plane array to passively observe the object at a first frame rate, and wherein said tracking camera images a smaller portion of said focal plane array to track the object at a second frame rate, faster than said first frame rate; and  
       a laser bore sighted with said infrared receiver and in communication with said processor, said processor activating said laser to direct a laser beam toward the object, whereupon said processor initiates a third frame rate, faster than said second frame rate, and said laser receiver monitors a returned laser beam signal from the object, wherein said processor receives said returned laser beam signal and images an even smaller portion of said focal plane array at an even faster third frame rate to observe the effect of said laser beam on the object.