Rocket exhaust driven amplification (REDA) of VLF waves in space

Patent metadata

Field	Value
Publication number	US-12006069-B2
Application number	US-202117547457-A
Country	US
Kind code	B2
Filing date	Dec 10, 2021
Priority date	Dec 15, 2020
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

A method and apparatus uses a VLF transmitter, a VLF receiver, and/or a low earth orbit satellite including a rocket engine. A VLF wave transmitted into space is converted to an ambient wave. The ambient wave acts as a signal wave for a whistler traveling wave parametric amplifier. Rocket exhaust is generated in atmospheric plasma. The rocket exhaust includes kinetic energy acting as a Lower Hybrid wave source. The Lower Hybrid wave source produces a Lower Hybrid wave, which acts as a pump wave for the parametric amplifier. Nonlinear mixing of the signal wave and the pump wave in the atmospheric plasma simultaneously parametrically amplifies the ambient wave and generates an idler wave and a parametrically amplified wave. The parametrically amplified wave (1) reduces the density of energetic protons or killer electrons in the Van Allen radiation belt, and (2) improves communications between the VLF transmitter and VLF receiver.

First claim

What is claimed as new and desired to be protected by Letters Patent of the United States is:

1. A method of using at least one Lower Hybrid wave source in atmospheric plasma to reduce a density of one of killer energetic protons and killer energetic electrons in a Van Allen radiation belt, the method comprising:
transmitting into space a very low frequency (VLF) wave using a VLF transmitter, the VLF wave being converted in space to an ambient wave, the ambient wave acting as a signal wave for a parametric amplifier; and
generating a Lower Hybrid wave in the atmospheric plasma using the at least one Lower Hybrid wave source, the Lower Hybrid wave acting as a pump wave for the parametric amplifier,
wherein nonlinear mixing of the signal wave and the pump wave in the atmospheric plasma simultaneously parametrically amplifies the ambient wave and generates an idler wave for the parametric amplifier and a parametrically amplified wave,
wherein, for the parametric amplifier, the pump wave comprises a frequency f 0 , the ambient wave comprises a frequency f 1 , and the idler wave comprises a frequency f 2 , the frequency f 0 being equal to a sum of the frequency f 1 ; and the frequency f2,
wherein the parametrically amplified wave reduces the density of one of the killer energetic protons and the killer energetic electrons in the Van Allen radiation belt,
wherein the method further comprises one of:
receiving directly the parametrically amplified wave using a VLF receiver, thereby improving long range communications between the VLF transmitter and the VLF receiver; and
receiving indirectly via reflection off an earth surface the parametrically amplified wave using the VLF receiver, thereby detecting underground structures.

2. The method according to claim 1 , wherein the Lower Hybrid wave source comprises one of:
a low earth orbit satellite comprising at least one rocket engine, the at least one rocket engine generating rocket exhaust in the atmospheric plasma, the rocket exhaust including a velocity substantially perpendicular to an earth magnetic field line, the rocket exhaust including kinetic energy acting as the Lower Hybrid wave source,
a high power radio frequency wave source in the atmospheric plasma, and
a signal generator attached to an antenna in the atmospheric plasma.

3. The method according to claim 1 , wherein the ambient wave comprises one of an ambient electromagnetic ion cyclotron (EMIC) wave and an ambient whistler-mode wave.

4. The method according to claim 1 , wherein the VLF transmitter comprises at least one of a fixed VLF transmitter, a mobile VLF transmitter, a ground VLF transmitter, an aerial VLF transmitter, and a space-based VLF transmitter.

5. The method according to claim 1 , wherein the VLF receiver comprises at least one of a fixed VLF receiver, a mobile VLF receiver, a space-based VLF receiver, a ground VLF receiver, an aerial VLF receiver, and an underwater VLF receiver.

6. The method according to claim 1 , wherein parametric amplification of the ambient wave by the nonlinear mixing of the signal wave and the pump wave in the atmospheric plasma is between about 30 dB and 50 dB.

7. The method of claim 6 , wherein, achieving the parametric amplification between about 30 dB and 50 dB comprises at least one rocket engine generating rocket exhaust, wherein the generating rocket exhaust comprises firing in atmospheric plasma the at least one rocket engine by at least one of:
increasing velocity of the rocket exhaust; and
increasing an amount of matter in the rocket exhaust.

8. The method according to claim 2 , wherein generating rocket exhaust comprises firing in atmospheric plasma the at least one rocket engine, said firing in the atmospheric plasma the at least one rocket engine comprising firing the at least one rocket engine at an altitude of about 400 to 600 kilometers above earth.

9. An apparatus comprising:
a very low frequency (VLF) transmitter transmitting a VLF wave into space, the VLF wave being converted in space to an ambient wave, the ambient wave acting as a signal wave for a parametric amplifier;
a Lower Hybrid wave source generating a Lower Hybrid wave in the atmospheric plasma, the Lower Hybrid wave acting as a pump wave for the parametric amplifier;
wherein nonlinear mixing of the signal wave and the pump wave in an atmospheric plasma simultaneously parametrically amplifies the ambient wave and generates an idler wave for the parametric amplifier and a parametrically amplified wave,
wherein, for the parametric amplifier, the pump wave comprises a frequency f 0 , the ambient wave comprises a frequency f 1 , and the idler wave comprises a frequency f 2 , the frequency f 0 being equal to a sum of the frequency f 1 and the frequency f 2 ,
wherein the parametrically amplified wave reduces a density of one of killer energetic protons and killer energetic electrons in a Van Allen radiation belt,
the apparatus further comprising a VLF receiver receiving the parametrically amplified wave, thereby improving long-range communications between said VLF transmitter and said VLF receiver.

10. The apparatus according to claim 9 , wherein the ambient wave comprises one of an ambient electromagnetic ion cyclotron (EMIC) wave and an ambient whistler-mode wave.

11. The apparatus according to claim 9 , wherein the VLF transmitter comprises at least one of a fixed VLF transmitter, a mobile VLF transmitter, a ground VLF transmitter, an aerial VLF transmitter, and a space-based VLF transmitter.

12. The apparatus according to 9 , wherein said VLF receiver comprises at least one of a fixed VLF receiver, a mobile VLF receiver, a space-based VLF receiver, a ground VLF receiver, and an underwater VLF receiver.

13. The apparatus according to claim 9 , wherein said Lower Hybrid wave source comprises one of:
a low earth orbit satellite comprising at least one rocket engine, said at least one rocket engine generating rocket exhaust in the atmospheric plasma, the rocket exhaust including a velocity substantially perpendicular to an earth magnetic field line, the rocket exhaust including kinetic energy acting as the Lower Hybrid wave source,
a high power radio frequency wave source in the atmospheric plasma, and a signal generator attached to an antenna in the atmospheric plasma.

Assignees

• Us Gov Sec Navy

Inventors

• Bernhardt Paul A

Classifications

• B64G1/54 Primary

  Protection against radiation · CPC title

• B64G1/401

  Liquid propellant rocket engines (Ion or plasma engines B64G1/413; Arcjets and other resistojets B64G1/415) · CPC title

• B64G1/413

  Ion or plasma engines · CPC title

• B64G1/242

  Orbits and trajectories · CPC title

• F03H1/0087

  Electro-dynamic thrusters, e.g. pulsed plasma thrusters · CPC title