Blocking jamming signals intended to disrupt communications

Patent metadata

Field	Value
Publication number	US-10826644-B2
Application number	US-201615048665-A
Country	US
Kind code	B2
Filing date	Feb 19, 2016
Priority date	Feb 19, 2016
Publication date	Nov 3, 2020
Grant date	Nov 3, 2020

Abstract

Jamming systems uses wireless signals (e.g., radio waves) to deliberately prevent a target from accurately receiving desired wireless signals. The examples herein disclose an anti-jamming system that mitigates an effect that jamming signals have on a radio receiver. To do so, the anti-jamming system generates a plasma shield in a region of space between the target and the jamming system. Plasma is opaque to electromagnetic energy meaning that radio signals, lasers, microwave energy, and the like are unable to pass through the plasma, and instead, are absorbed by the plasma. As such, the jamming signals emitted by the jamming system are absorbed by the plasma shield and do not interfere with the target's radio receiver.

First claim

What is claimed is:

1. An anti-jamming system, comprising:
a pulsed laser source;
a detector configured to detect a jamming signal and identify a path traversed by the jamming signal; and
an optical control system configured to, in response to the detector detecting the jamming signal, direct laser signals emitted by the pulsed laser source to generate a moveable plasma shield in a plasma shield region located along the path traversed by the jamming signal in order to block the jamming signal from reaching a communication system.

2. The anti-jamming system of claim 1 , wherein the optical control system is configured to, during each pulse of the pulsed laser source, deflect a respective one of the laser signals to a defined sub-portion of the plasma shield region, wherein the plasma shield region is divided into a plurality of sub-portions.

3. The anti-jamming system of claim 2 , wherein the optical control system is configured to, using a plurality of pulses of the pulsed laser source, generate the plasma shield region by rastering the pulsed laser source in a predefined pattern through the plurality of sub-portions.

4. The anti-jamming system of claim 3 , wherein the optical control system further comprises a beam steering mechanism configured to deflect the laser signals to raster the pulsed laser source in the predefined pattern.

5. The anti-jamming system of claim 2 , wherein the optical control system is configured to generate the plasma shield in multiple sub-portions of the plurality of sub-portions simultaneously by splitting a laser signal emitted during a single pulse of the pulsed laser source into separate laser signals that each focus onto a respective one of the multiple sub-portions.

6. The anti-jamming system of claim 5 , wherein the optical control system comprises a lenslet configured to split the laser signal emitted during the single pulse into the separate laser signals.

7. The anti-jamming system of claim 1 , further comprising a lens configured to focus the laser signals to establish the plasma shield region at a predefined distance from the communication system.

8. A system comprising:
a jamming signal detector configured to detect a jamming signal configured to interfere with a communication system and identify a path traversed by the jamming signal;
a laser source; and
an optical control system configured to, in response to detecting the jamming signal, direct a laser signal emitted by the laser source to generate a moveable plasma shield in a plasma shield region along the path traversed by the jamming signal that blocks the jamming signal from reaching the communication system.

9. The anti-jamming system of claim 1 , wherein the detector is further configured to:
detect a plurality of jamming signals,
determine, from the plurality of jamming signals, a first jamming signal which carries the largest amount of power, and
identify a path traversed by the first jamming signal.

10. The system of claim 8 , wherein the laser source does not emit the laser signal until the jamming signal is detected using the jamming signal detector.

11. The system of claim 8 , wherein the laser source is a pulsed laser source and the plasma shield region is divided into a plurality of sub-portions, wherein the optical control system is configured to generate plasma in only one of the plurality of sub-portions during each pulse of the laser source.

12. The system of claim 8 , wherein the laser source is a pulsed laser source and the plasma shield region is divided into a plurality of sub-portions, wherein the optical control system is configured to generate plasma in multiple sub-portions of the plurality of sub-portions during each pulse of the laser source.

13. The system of claim 8 ,
wherein the communication system comprises an antenna configured to transmit communication signals while the moveable plasma shield is generated.

14. The system of claim 13 , wherein the communication system is configured to, in response to detecting the jamming signal, adjust a parameter to avoid the moveable plasma shield when transmitting the communication signals.

15. A method, comprising:
detecting a jamming signal configured to interfere with a communication system;
identifying a path traversed by the jamming signal; and
generating, in response to detecting the jamming signal, a moveable plasma shield in a plasma shield region disposed in the path on which the jamming signal traverses to block the jamming signal from reaching the communication system.

16. The method of claim 15 , wherein identifying the path traversed by the jamming signal comprises determining a propagation direction of the jamming signal using a detector that receives the jamming signal.

17. The method of claim 15 , further comprising:
adjusting, in response to generating the moveable plasma shield, a parameter to avoid the moveable plasma shield when transmitting communication signals using the communication system.

18. The method of claim 15 , wherein generating the moveable plasma shield in the plasma shield region further comprises:
rastering a pulsed laser source generating the moveable plasma shield in a predefined pattern to generate the plasma shield region, wherein the predefined pattern divides the plasma shield region into a plurality of sub-portions.

19. The method of claim 18 , wherein generating the moveable plasma shield in the plasma shield region further comprises:
repeating the predefined pattern using the pulsed laser source before the plasma in any one of the plurality of sub-portions completely disappears.

20. The method of claim 15 , wherein generating the moveable plasma shield in the plasma shield region further comprises:
splitting a laser signal into a plurality of separate laser signals;
focusing each of the separate laser signals onto respective sub-portions of the plasma shield region, wherein the separate laser signals generate plasma in the sub-portions simultaneously.

Assignees

• Boeing Co

Inventors

• Hunt Jeffrey H

Classifications

• H04K3/68

  using passive jamming, e.g. by shielding or reflection (shielding of apparatus or components against electric or magnetic field H05K9/00) · CPC title

• H04K3/224 Primary

  with countermeasures at transmission and/or reception of the jammed signal, e.g. stopping operation of transmitter or receiver, nulling or enhancing transmitted power in direction of or at frequency of jammer · CPC title