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This dissertation presents results and analysis regarding the use of anthropogenic ground-based and space-based Very Low Frequency (VLF) transmitters to precipitate energetic electrons in the inner radiation belt. While existing ground-based VLF transmitters already precipitate energetic electrons, they do so inadvertently. In this work, we consider sources designed specifically for the purpose of precipitating >100 keV electrons. This concept is termed controlled precipitation. We focus on this energy range because these electrons are most damaging from a so-called space weather perspective. We initially consider the distribution of whistler-mode wave energy from space-based sources distributed in L-shell and geomagnetic latitude. We also incorporate the effects of VLF antenna radiation immersed in a magnetoplasma. Our results demonstrate that a space-based source, by varying the frequency of the injected waves, can target L-shells both higher and lower than the source site, with wave frequencies below (above) the local lower hybrid resonance frequency moving to higher (lower) L-shells. We show that only three sources placed at various locations in the inner magnetosphere are required to project wave power over the range 1.41 MeV electron precipitation. Compared to a single-pass interaction, highly oblique magnetospherically reflecting whistler-mode waves precipitate up to 16 times more 100 keV to 5 MeV electrons. Waves injected at initial wave normal angles closer to the magnetic field, e.g., 45, in fact precipitate fewer >1 MeV electrons than waves injected close to the resonance cone. We also investigate the tradeoffs among source location, operating frequency and radiated power for ground-based VLF sources designed to precipitate energetic electrons in the inner radiation belts. We determine energetic electron precipitation signatures induced by five existing ground-based VLF sources as well as five different hypothetical transmitters distributed broadly in geomagnetic latitude with a wide range of operating frequencies. We show that source location affects induced precipitation more strongly than operating frequency or radiated power. Sources located at 35 to 45 induce the most >100 keV precipitation for the 10 to 40 kHz waves typical of ground-based VLF sources, while locations below lambda≃15 or above lambda≃55 are least effective at precipitating energetic electrons. In all cases, induced precipitation increases as the operating frequency decreases, with 10 kHz waves from a source at lambda≃35 the most effective at precipitating >100 keV electrons. Precipitation signatures produced by five existing ground-based VLF transmitters are also simulated: the NAA, NLK, NAU, NPM, and NWC VLF transmitters. Among these, the NWC transmitter located at a geomagnetic latitude of 31.7 in western Australia induces the strongest >100 keV electron precipitation signature, followed by the NPM, NAU, NAA and NLK transmitters.

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