Granted Patent B2

US 10,126,101 · App. 15/269,601 · Granted Nov 13, 2018

Inventor: Todd Ell (Savage, MN)

Assignee: Rosemount Aerospace Inc.

F41G7/26F41G3/145F41G7/008F41G7/226F41G7/2246F41G7/2293

Abstract

Claims (56)

1. A dual-mode seeker for a guided missile, the dual-mode seeker comprising:

a first-mode target locator configured to:

detect laser pulses reflected by a target within a scene aligned along a missile axis, each of the laser pulses projected onto the target by a remote Laser Target Designator (LTD) thereby designating the target;

determine, based on the detected laser pulses, a direction of the designated target relative to the optical axis; and

generate an output signal indicative of the direction of the designated target relative to the missile axis;

a second-mode target locator configured to:

capture Short-Wavelength InfraRed (SWIR) images of the aligned scene, each of the SWIR images captured at an exposure time period in which the remote LTD is not projecting a laser pulse onto the designated target;

identify an image feature within each of the SWIR images, the image feature corresponding to the designated target;

determine, based on the identified image feature, the direction of the designated target relative to the missile axis; and

generate an output signal indicative of the direction of the designated target relative to the missile axis; and

an active SWIR illuminator aligned parallel to the missile axis and configured to:

illuminate the designated target during an illumination time offset by a Phase Offset Interval (POI) from the exposure time period.

2. The dual-mode seeker of claim 1 , wherein illuminating the designated target during the illumination time period offset by the POI from the exposure time period is detectable by the remote LTD to indicate that the dual-mode seeker has identified the image feature corresponding to the designated target.

3. The dual-mode seeker of claim 1 , wherein the designated target is illuminated by the active SWIR illuminator during the exposure time period of at least one of the SWIR images.

4. The dual-mode seeker of claim 1 , wherein the first-mode target locator is further configured to:

identify, based on the detected laser pulses, a Pulse Repetition Interval (PRI) at which the remote LTD projects the laser pulses onto the target within the scene.

5. The dual-mode seeker of claim 4 , wherein the first-mode target locator is further configured to:

interpret, based on the identified PRI, communications from the LTD.

6. The dual-mode seeker of claim 5 , wherein the first-mode target locator is further configured to:

generate, based on the interpreted communications, an abort command or a retargeting command.

7. The dual-mode seeker of claim 1 , wherein the first-mode target locator is further configured to:

predict, based on the detected laser pulses, a time interval corresponding to a future laser pulse projected by the remote LTD of the designated target within the aligned scene.

8. The dual-mode seeker of claim 1 , wherein the second-mode target locator is further configured to:

continue, after identifying the image feature within each of the SWIR images, the capturing, identifying, determining and generating steps of the second-mode target locator in a repetitious fashion.

9. A Laser Target Designator (LTD) for a guided missile, the LTD comprising:

a laser configured to:

project laser pulses onto a target aligned along a laser axis, thereby designating the target, the laser pulses projected at a Pulse Frequency Rate (PFR); and

a Short-Wavelength InfraRed (SWIR) camera configured to:

capture SWIR images of a scene aligned along the laser axis;

detect SWIR illumination pulses of the designated target by a target illuminator of a guided missile; and

identify a Pulse Offset Interval (POI) between the projected laser pulses and the detected SWIR illumination pulses.

10. The LTD of claim 9 , wherein the SWIR camera is further configured to:

generate an output signal indicative that the POI corresponds to a predetermined interval.

11. The LTD of claim 9 , wherein the SWIR camera is further configured to:

display, on a display screen, indicia indicative the detected SWIR illumination pulses.

12. The LTD of claim 9 , wherein the laser is further configured to:

project secondary laser pulses onto the aligned target at a Secondary Offset Interval (SOI) between the detected SWIR illumination pulses and the projected secondary laser pulses.

13. The LTD of claim 9 , wherein projecting secondary laser pulses is indicative of a retargeting command or an abort command.

14. A method of tracking a target for a guided missile, the method comprising:

detecting laser pulses reflected by a designated target;

determining based on the detected laser pulses, a direction of the designated target;

capturing Short-Wavelength InfraRed (SWIR) images of a scene that includes the designated target, each of the SWIR images captured at an exposure time period in which laser pulses are not being projected onto the designated target;

identifying an image feature within each of the SWIR images, the image feature corresponding to the designated target;

determining, based on the identified image feature, the direction of the designated target;

generating an output signal indicative of the direction of the designated target; and

illuminating the designated target during an illumination time offset by a Phase Offset Interval (POI) from a time period corresponding to the detected laser pulses.

15. The method of claim 14 , wherein illuminating the designated target during the illumination time period offset by the POI from the time period corresponding to the detected laser pulses communicates to a remote Laser Target Detector (LTD) that the image feature corresponding to the designated target has been identified.

16. The method of claim 14 , wherein the illumination time period coincides with the exposure time period.

17. The method of claim 14 , further comprising:

identifying, based on the detected laser pulses, a Pulse Repetition Interval (PRI) at which a remote LTD designates the target within the scene.

18. The method of claim 17 , further comprising:

interpreting, based on the identified PRI, communications from the LTD.

19. The method of claim 18 , further comprising:

generating, based on the interpreted communications, an abort command or a retargeting command.

20. The method of claim 14 , further comprising:

predicting, based on the detected laser pulses, a time interval corresponding to a next designation by a remote LTD of the designated target within the aligned scene.

Assignments (11)

Continuity (1)

Cited By (2)

US 12,480,763 US 12,618,646