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Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov

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Mostly effective for generation at lover VLF (1-10 kHz). Main restrictions : at altitudes > 80 km 2. Sporadic character of electrojet events. Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov - PowerPoint PPT Presentation
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Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov 1. Modulation of ionospheric currents by powerful RF radiation Firstly detected VLF signal Summary of Tromsǿ results Typical experimental scheme 1 eH em Mostly effective for generation at lover VLF (1-10 kHz) Main restrictions: 1. at altitudes > 80 km 2. Sporadic character of electrojet events
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Page 1: Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov

Comparison of different methods of VLF/ELF/ULF radio waves generationD.S. Kotik & S.V. Polaykov

1. Modulation of ionospheric currents by powerful RF radiation

Firstly detected VLF signal

Summary of Tromsǿ results

Typical experimental scheme

1eH

em

 

Mostly effective for generation at lover VLF (1-10 kHz)

Main restrictions: 1. at altitudes > 80 km

2. Sporadic character of electrojet events

Page 2: Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov

2. Moving ionospheric source.

h~80km

x

H1 H2 d1=100(200)m

e -iωte –i (ωt+/-Ώ)t

(+)(-)

op1 op2R1=30km R2=300km

 

;

)cos(2021

kd

hV

h

dkXtEEEJ

ph

nonlinear

)12(6/2 kHzkhzhfdF

)12(6/2 kHzkhzhfdF

Page 3: Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov

3. VLF Production by HF Heating Using the Thermal Cubic Nonlinearity

h~80km

H1 H2d1=100m

e -iωte –i (2ωt+/-Ώ)t

op1 R1=30km

Nonlinear nonresomance current:

The magnification factor is -- 2

22

H

1

0

E

E

j

j eH

cubic

thermal

Comparison with electrojet modulation method gives by ratio

01.19.1990f1=4.63 MHzP1=250 kWf2=9.05 MHzP2 =500 kW X polarization O polarization

em

Page 4: Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov

4. ELF generation using 1 MWt broadcasting stations. 

N. Novgorod

S. Petersburg

Lovo.

R=1300km

● Moscow

An example of correlation of signal amplitude received at NN with magnetic field variations on the Apatity for case KP-5+

The case of week disturbance (KP=20)

)exp(2

4

2

kh

MkН

kWPP radW2002.0~

Page 5: Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov

To Barentsburg, 1200km

5. ULF generation using power lines

Sodankyla data (distance 500 km)HE-W component.

AverageULF spectrum for HN-S

Hautavaara, 00:03-03:00 LT, 28.09.01.

Lovozero

Geometry of the experiment

Page 6: Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov

δ

CONTROLLER

Matchingcapacitors

ULF generator-converter

R

Precisiongenerator

power~380V50Hz

Power line 108 km longPower plant

~380kV

Consumers

5. EXPERIMENTAL INSTALLATIONS

.02

For F = 10 Hz δ ~ 6-8 km

Page 7: Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov

1.0E-09

1.0E-08

1.0E-07

1.0E-06

1.0E-05

1.0E-04

0 500 1000 1500 2000 2500 3000 3500 4000

0 45 90 Hi,SURA(800) Hi,TRMSO(800)

7. CONCLUSIONS

Magnetic field distance dependence for Kola ground based ULF facility (for three azimuth

directions) and for SURA and Tromso ionospheric ULF

antennas at 40 Hz radiated frequency.

BAND 

METHOD APPLIANCEFIELDS

Low VLF1 –10 kHz

Direct modulation of ionospheric currents by RF heaters

Diagnostic of low Ionosphere, studying of propagation in E-I waveguide

High VLF 10 –20 kHz

1. Moving source, 2. Thermal cubic nonlinearity. Both using heaters with complicate arrays

Diagnostic of low Ionosphere, studying of E-I waveguide,injection intomagnetosphere

ELF0.1 – 1 kHz

Direct modulation of ionospheric currents by powerful broadcasting stations

Diagnostic of low Ionosphere, studying of E-I waveguide,Earth exploration for geoengineering

ULFbelow 100Hz

Long power lines with ULF generator

Diagnostic of low Ionosphere, studying of E-I waveguide,Deep Earth exploration Studying of nearEarth ULF resonators injection intomagnetosphere

Page 8: Comparison of different methods of VLF/ELF/ULF radio waves generation D.S. Kotik & S.V. Polaykov

The estimated and experimentally confirmed zone of assured ULF signal detection for ULFRAD.

 

3.5 4 4.5 5 5.52

4

6

8

10

12

14

McIlwain parameter, L

pro

ton g

yro

frequency,

Hz

The ULFRAD concept 


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