1. Stolarczyk, L. G., "Detection and imaging of underground structures by exploiting ELF/VLF radiowaves,", AFRL-VS-TR-2000-1583, 2000.
doi:10.1109/JOE.2013.2278932 Google Scholar
2. Doniec, M., M. Angermann, and D. Rus, "An end-to-end signal strength model for underwater optical communications," IEEE Journal of Oceanic Engineering, Vol. 38, 743-757, 2013.
doi:10.1109/TAP.2012.2207682 Google Scholar
3. Wang, Y.-X., R.-H. Jin, X.-L. Liang, and J.-P. Geng, "Propagation of SLF/ELF electromagnetic waves excited by an underground HED in the lower ionosphere," IEEE Transactions on Antennas and Propagation, Vol. 60, No. 11, 5412-5418, 2012.
doi:10.1002/2015RS005683 Google Scholar
4. Maxworth, A. S., M. Golkowski, M. B. Cohen, et al. "Multistation observations of the azimuth, polarization, and frequency dependence of ELF/VLF waves generated by electrojet modulation," Radio Science, Vol. 50, 1008-1026, 2015.
doi:10.1007/s11141-015-9590-5 Google Scholar
5. Titova, E. E., A. G. Demekhov, A. A. Mochalov, et al. "ELF/VLF perturbations above the HAARP transmitter recorded by the Demeter satellite in the upper ionosphere," Radiophysics and Quantum Electronics, Vol. 58, 155-172, 2015.
doi:10.1029/RS025i006p01311 Google Scholar
6. Papadopoulos, K., C. L. Chang, P. Vitello, et al. "On the efficiency of ionospheric ELF generation," Radio Science, Vol. 25, 1311-1320, 1990. Google Scholar
7. Kuo, S., A. Snyder, P. Kossey, et al. "Beating HF waves to generate VLF waves in the ionosphere," Journal of Geophysical Research Space Physics, Vol. 117, 1-83, 2012. Google Scholar
8. Moore, R. C., S. Fujimaru, M. Cohen, et al. "On the altitude of the ELF/VLF source region generated during ``beat-wave'' HF heating experiments," Geophysical Research Letters, Vol. 39, No. 18, L18101, 2012.
doi:10.1029/91GL02544 Google Scholar
9. Barr, R. and P. Stubbe, "On the ELF generation efficiency of the Tromsø Heater Facility," Geophysical Research Letters, Vol. 18, 1971-1974, 1991.
doi:10.1002/2013RS005336 Google Scholar
10. Fedorenko, Yu, E. O. Tereshchenko, S. Pilgaev, et al. "Polarization of ELF waves generated during ``beat-wave'' heating experiment near cutoff frequency of the Earth-ionosphere waveguide," Radio Science, Vol. 49, 1254-1264, 2014.
doi:10.1002/2014GL060376 Google Scholar
11. Tereshchenko, E. O., O. I. Shumilov, E. A. Kasatkina, et al. "Features of amplitude and Doppler frequency variation of ELF/VLF waves generated by ``beat-wave'' HF heating at high latitudes," Geophysical Research Letters, Vol. 41, 4442-4448, 2014.
doi:10.1134/S0016793215040040 Google Scholar
12. Gavrilov, B. G., Yu I. Zetser, I. A. Ryakhovskii, et al. "Remote sensing of ELF/VLF radiation induced in experiments on artificial modification of the ionosphere," Geomagnetism and Aeronomy, Vol. 55, 450-456, 2015.
doi:10.1109/JRPROC.1957.278469 Google Scholar
13. Wait, J. R., "The mode theory of VLF ionospheric propagation for finite ground conductivity," Proceedings of the IRE, Vol. 45, 760-767, 1957.
doi:10.1109/TAP.1968.1139277 Google Scholar
14. Galejs, J., "ELF and VLF fields of a horizontal electric dipole," IEEE Transactions on Antennas and Propagation, Vol. 16, 689-700, 1968. Google Scholar
15. Pan, W., Propagation of Long Wave Very Long Wave and Extremely Long Wave, University of Electronic Science and Technology Press, 2004.
16. Chang, S., Z. Zhao, and F. Wang, "The downward ELF/VLF waves radiation excited by ionospheric artificial modulation," Chinese Journal of Geophysics, Vol. 10, 2458-2467, 2011. Google Scholar
17. Wang, F., "Ray tracing of extremely low frequency waves radiated from ionospheric artificial modulation at low latitude," Acta Phys Sin, Vol. 19, 199401-199401, 2012. Google Scholar
18. Huang, W. and S. Gu, "Interaction between the powerful high-frequency radio wave and the lower terrestrial ionosphere," Chinese Journal of Space Science, Vol. 3, 181-188, 2003. Google Scholar
19. Li, K. and Y. Miao, "The VLF field of the sea surface generated by the transmitter antenna in the inhomogeneous ionosphere," Chinese Journal of Radio Science, Vol. 13, 265-269, 1998.
doi:10.1029/RS019i004p01111 Google Scholar
20. Barr, R. and P. Stubbe, "ELF and VLF radiation from the ``polar electrojet antenna''," Radio Science, Vol. 19, 1111-1122, 1984.
doi:10.1016/S1364-6826(96)00121-6 Google Scholar
21. Barr, R. and P. Stubbe, "ELF and VLF wave generation by HF heating: A comparison of AM and CW techniques," Journal of Atmospheric and Solar-Terrestrial Physics, Vol. 59, 2265-2279, 1997. Google Scholar
22. Kou, S. P., M. C. Lee, P. Kossey, et al. "Stimulated thermal instability for ELF and VLF wave generation in the polar electrojet," Geophysical Research Letters, Vol. 27, 85-88, 2000. Google Scholar
23. Cohen, M. B., R. C. Moore, M. Golkowski, et al. "ELF/VLF wave generation from the beating of two HF ionospheric heating sources," Journal of Geophysical Research Space Physics, Vol. 117, 1702-1711, 2012. Google Scholar
24. Chang, S. S., Z. Y. Zhao, and F. Wang, "The downward ELF/VLF waves radiation excited by ionospheric artificial modulation," Chinese Journal of Geophysics, Vol. 10, 2458-2467, 2011. Google Scholar