Multi-zone approach for active/passive sensing

• US 8,934,087 B1
• Filed: 04/30/2012
• Issued: 01/13/2015
• Est. Priority Date: 04/29/2011
• Status: Active Grant

• Current Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc)
• Original Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc)
• Inventors: Stobie, James A., Wright, Harold T.
• Primary Examiner(s): RATCLIFFE, LUKE D
• Application Number:
  US13/460,155
• Time in Patent Office: 988 Days
• Field of Search: 356 301- 315, 356 401- 41, 356 501- 51, 356 6- 22, 356/28, 356/28.5
• US Class Current: 356/4.01
• CPC Class Codes: G01J 5/10 using electric radiation detectors
• CPC Class Codes: G01J 5/20 using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices
• CPC Class Codes: G01S 17/18 wherein range gates are used
• CPC Class Codes: G01S 7/483 Details of pulse systems
• CPC Class Codes: G01S 7/495 Counter-measures or counter-counter-measures using electronic or electro-optical means
• CPC Class Codes: H04K 2203/14 for the transfer of light or images, e.g. for video-surveillance, for television or from a computer screen
• CPC Class Codes: H04K 2203/24 for communication related to weapons
• CPC Class Codes: H04K 3/41 characterized by the control of the jamming activation or deactivation time control of jamming activation and deactivation time only for the purpose of alternating between jamming mode and target monitoring mode H04K3/45
• CPC Class Codes: H04K 3/45 characterized by including monitoring of the target or target signal, e.g. in reactive jammers or follower jammers for example by means of an alternation of jamming phases and monitoring phases, called "look-through mode"
• CPC Class Codes: H04K 3/825 by jamming
• CPC Class Codes: H04N 25/20 for transforming only infrared radiation into image signals
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

Techniques are disclosed for providing a multi-zone sensing array configured for use in a dual-mode active/passive sensor system. In some embodiments, the techniques can be used to minimize or otherwise reduce power dissipation in sensor arrays, while further providing the ability to readout the active returns rapidly. The techniques can be implemented, for example, by using the full N×M array format for target acquisition in a passive imaging mode, and then, with the aid of a gimbal for instance, place the region-of-interest in a subset of the array configured with dual-mode active/passive pixel receivers to provide three-dimensional imaging. Such techniques are capable of, for example, supporting both active and passive operating modes of a countermeasure system.

Claims

1. An imaging device, comprising:

a sensor array of M×

N pixels, wherein all available M×

N pixels are used for imaging of a target during a passive mode, and a subset of the available M×

N pixels is used for imaging during an active mode, wherein the subset of the available M×

N pixels is less than all available M×

N pixels; and

a readout circuit operatively coupled to the M×

N sensor array, wherein each pixel of the array is associated with an input cell of the readout circuit, and the input cells associated with the subset of the available M×

N pixels are configured differently than the other available input cells, and wherein in the active mode, input cells not associated with the subset of the available M×

N pixels can be powered down.

2. The device of claim 1 wherein the active mode is used for both wide field of view (WFOV) and narrow field of view (NFOV) imaging.

3. The device of claim 1 wherein the passive mode is used for WFOV imaging.

4. The device of claim 1 wherein in the active mode, input cells not associated with the subset of the available M×

N pixels are powered down.

5. The device of claim 1 further comprising:

a gimbal for placing and maintaining the target within a region of the sensor array defined by the subset of the available M×

N pixels.

6. The device of claim 1 wherein the subset of the available M×

N pixels is used in both the passive and active modes.

7. The device of claim 1 wherein the input cells associated with the subset of the available M×

N pixels are configured as high-speed active input cells, and a corresponding speed of the other available input cells is slower.

8. The device of claim 1 wherein the device supports both active ranging in the active mode and passive tracking in the passive mode.

9. The device of claim 8 wherein the active ranging includes both coarse and fine resolution ranging.

10. The device of claim 1 wherein passive acquisition of the target by the device has a set passive mode integration time, thereby leaving a remainder of a Master Frame period for active ranging.

11. The device of claim 10 wherein the active ranging includes receiving multiple active range gate samples via one or more of the available M×

N pixels in the subset.

12. A system-on-chip comprising the imaging device of claim 1.

13. A countermeasure system comprising the imaging device of claim 1.

14. A directed infrared countermeasure system, comprising:

a sensor array of M×

N pixels, wherein all available M×

N pixels are used for detecting infrared radiation of a target during a passive mode, and a subset of the available M×

N pixels is used for detecting during the passive mode and an active mode, wherein the subset is less than all available M×

N pixels;

a readout circuit operatively coupled to the M×

N sensor array, wherein each pixel of the array is associated with an input cell of the readout circuit, and the input cells associated with the subset of the available M×

N pixels are configured differently than the other available input cells, and wherein in the active mode, input cells not associated with the subset of the available M×

N pixels can be powered down;

a laser for providing transmitted laser pulses during the active mode; and

a gimbal for placing and maintaining the target within a region of the sensor array defined by the subset of the available M×

N pixels.

15. The system of claim 14 wherein the active mode is used for both wide field of view (WFOV) and narrow field of view (NFOV) detecting and the passive mode is used for WFOV detecting.

16. The system of claim 14 wherein in the active mode, input cells not associated with the subset of the available M×

N pixels are powered down.

17. The system of claim 14 wherein the input cells associated with the subset of the available M×

N pixels are configured as high-speed active input cells, and a corresponding speed of the other available input cells is slower.

18. The system of claim 14 wherein the system supports both active ranging in the active mode and passive tracking in the passive mode, and the active ranging includes both coarse and fine resolution ranging.

19. A countermeasure system, comprising:

a sensor array of M×

N pixels, wherein all available M×

N pixels are used for detecting infrared radiation of a target during a passive mode, and a subset of the available M×

N pixels is used for detecting during the passive mode and an active mode, wherein the active mode is used for both wide field of view (WFOV) and narrow field of view (NFOV) detecting and the passive mode is used for WFOV detecting;

a readout circuit operatively coupled to the M×

N sensor array, wherein each pixel of the array is associated with an input cell of the readout circuit, and the input cells associated with the subset of the available M×

N pixels are configured as high-speed active input cells, and a corresponding speed of the other available input cells is slower;

a laser for providing transmitted laser pulses during active mode ranging; and

a gimbal for placing and maintaining the target within a region of the sensor array defined by the subset of the available M×

N pixels;

wherein the system supports both active ranging in the active mode and passive tracking in the passive mode, and the active ranging includes both coarse and fine resolution ranging, and the active ranging includes receiving multiple active range gate samples via one or more of the available M×

N pixels in the subset.

20. The system of claim 19 wherein in the active mode, input cells not associated with the subset of the available M×

N pixels can be powered down.