Adaptive communications focal plane array

Patent metadata

Field	Value
Publication number	US-9929815-B1
Application number	US-201715616532-A
Country	US
Kind code	B1
Filing date	Jun 7, 2017
Priority date	Jun 6, 2017
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

Adaptive communications focal plane arrays that may be implemented in, e.g., a specially-configured camera that can be utilized to receive and/or process information in the form of optical beams are presented. A specialized focal plane array (FPA) having a plurality of optical detectors is utilized, where one or more optical detectors are suppressed such that data is not allowed to be output from the one or more suppressed optical detectors, and only a significantly smaller number or subset of optical detectors receiving optical beams are allowed to output data. In this way, the rate at which data is to be output by an adaptive communications FPA (ACFPA) can be significantly reduced.

First claim

What is claimed is:

1. An optical communications camera array comprising a plurality of optical communications cameras, wherein electronic inputs and outputs of each optical communications camera are interfaced with a single optical receiver assembly control electronics, and wherein each optical communications camera comprises:
an imaging lens and an adaptive communications focal plane array, wherein an optically sensitive surface of the adaptive communications focal plane array lies in a focal plane of the imaging lens, the adaptive communications focal plane array comprising:
a plurality of optical detectors, a subset of which receive one or more optical beams transmitted by one or more optical transmitter assemblies;
a plurality of signal discrimination circuits, each of which is operatively connected to a corresponding one of the plurality of optical detectors, and performs the following:
detects the presence of an optical beam that is currently being received by its corresponding optical detector;
computes an estimated signal-to-noise ratio associated with an optical beam it has detected;
sets a value of the estimated signal-to-noise ratio to a set value when it has not detected the presence of the optical beam;

a plurality of switching circuits, each of which is operatively connected to a corresponding one of the plurality of optical detectors and a corresponding one of the plurality of signal discrimination circuits, wherein each of the plurality of switching circuits controls a flow of information being received in the form of an optical beam, outputs a location relative to other optical detectors of the plurality of optical detectors indicative of the corresponding optical detector receiving the optical beam, and outputs the estimated signal-to-noise ratio provided by its corresponding signal discrimination circuit; and
an analog output detector operatively connected to each of the plurality of switching circuits, the analog output detector informing each of the plurality of switching circuits whether or not information being received by an optical detector from an optical beam is currently being output by any one of the plurality of switching circuits.

2. The optical communications camera array of claim 1 , wherein analog outputs from all of the plurality of switching circuits of all the adaptive communications focal plane arrays are combined electronically, and wherein the combination of analog outputs is input to a digital signal converter, the output of the digital signal converter being input to the optical receiver assembly control electronics.

3. The optical communications camera array of claim 2 , wherein the optical receiver assembly control electronics initiates the process of receiving and extracting information embedded in a first optical beacon by sending a command to all of the plurality of adaptive communications focal plane arrays except a first one causing an output from each switching circuit in each of the adaptive communications focal plane arrays to be suppressed.

4. The optical communications camera array of claim 3 , wherein, following suppression of outputs from all switching circuits in adaptive communications focal plane arrays other than the first one, the optical receiver assembly control electronics sends an optical beacon receiver initialization command to the first adaptive communications focal plane array to activate a switching circuit associated with only one optical detector in the first adaptive communications focal plane array, information from an optical beam that its associated optical detector is receiving from an optical transmitter assembly being output to the optical receiver assembly control electronics.

5. The optical communications camera array of claim 4 , wherein following the activation of the switching circuit associated with a first optical detector in the first adaptive communications focal plane array, the optical receiver assembly control electronics issues commands to activate a plurality of switching circuits associated with other optical detectors that are receiving the same optical beam as the first optical detector within the adaptive communications focal plane arrays, outputs from the other optical detectors being combined with an original output from the first optical detector.

6. The optical communications camera array of claim 5 , wherein identifying information associated with an optical transmitter assembly that is sending optical beam information is extracted from the optical beacon portion of the optical beam by the optical receiver assembly control electronics to which the optical beam information is currently being output.

7. The optical communications camera array of claim 6 , wherein the optical receiver assembly control electronics periodically performs a re-centering procedure by periodically estimating the current angular position of the optical transmitter assembly within the optical communications camera array's field of view using values of the focal-plane locations of the optical detectors from which optical beam information is currently being output to the optical receiver assembly control electronics, along with the most recent estimate of the signal to noise ratio of the optical beam information being output by each such optical detector.

8. The optical communications camera array of claim 7 , wherein the optical receiver assembly control electronics continues to periodically estimate the current angular position of an optical transmitter assembly from which all the identifying information has already been extracted from values of the estimated signal to noise ratio and values of the focal-plane locations of the optical detectors that are currently receiving optical beam information from that optical transmitter assembly, but for which output has been suppressed by deactivating the switching circuits associated with each of these optical detectors.

9. The optical communications camera array of claim 8 , wherein the output of optical beams is suppressed from one or more optical transmitter assemblies from which identifying information has already been extracted from their optical beacons, and wherein the current angular location of these output-suppressed optical transmitter assemblies continues to be periodically updated, while commands are issued resulting in a plurality of switching circuits associated with optical detectors that are receiving the optical beam transmitted by a different optical transmitter assembly being activated within a plurality of the adaptive communications focal plane arrays, thereby causing the output from each of these optical detectors to be combined, thereby providing an optical beam output to the optical receiver assembly control electronics having a signal to noise ratio that is higher than it would be if only a smaller number of these detector outputs were combined.

10. The optical communications camera array of claim 9 , wherein identifying information associated with an optical transmitter assembly that is sending optical beam information is extracted from the optical beacon portion of the optical beam by the optical receiver assembly control electronics to which the optical beam information is currently being output.

11. The optical communications camera array of claim 2 , wherein the optical receiver assembly control electronics outputs the optical beacon information received from one or more optical transmitter assemblies to an augmented reality device, the augmented reality device presenting one or more aspects of the optical beacon information in an augmented reality presentation displayed to a user of the augmented reality device.

12. The optical communications

Assignees

• Surefire Llc

Inventors

• Bortz John C
• Shatz Narkis

Classifications

• H04B10/116 Primary

  Visible light communication · CPC title

• G11B7/00

  Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation {by modifying optical properties or the physical structure}, reproducing using an optical beam at lower power {by sensing optical properties}; Record carriers therefor (G11B11/00, G11B13/00 take precedence) · CPC title

• H04B10/691 Primary

  Arrangements for optimizing the photodetector in the receiver · CPC title

• G06K19/06

  characterised by the kind of the digital marking, e.g. shape, nature, code · CPC title

• H04B10/11

  Arrangements specific to free-space transmission, i.e. transmission through air or vacuum · CPC title