INVESTIGATION OF ELF RADIATION GENERATED BY ARTIFICIALLY MODULATED IONOSPHERE AND ITS APPLICABILITY TO COMMUNICATION TO SUBMARINES
电离层人工调制的极低频辐射和在潜艇通信中的应用探讨

Powerful HF waves modulated by ELF signals are employed to heat the lower ionosphere and generate ELF radiations that might be applicable to communication to submarines. Numerical results show that, if the frequency and effective radiation power(ERP) of the HF waves are 5MHz and 100MW respectively, with modulation frequency 100Hz, then the attenuation rates of the Quasi-TEM propagating in the earth-ionosphere waveguide are usually less than IdB/Mm, and the magnetic field strength 1000km away from the heating location is in the order of 10-8A/m. As for communication to submarines, for a specific ELF source and a given submarine location, there exists a most favorable frequency that maximizes the receiving signals.