Unmanned airborne vehicle (UAV): Flight testing and evaluation of two-channel E-field very low frequency (VLF) instrument

摘要

Using VLF frequencies, transmitted by the Navy's network, for airborne remote sensing of the earth's electrical, magnetic characteristics was first considered by the United States Geological Survey (USGS) around the mid 1970s. In the mid 1990s, the Branch of Geophysics designed and developed a two-channel E-field ground portable VLF system. The system was built using state-of-the-art circuit components and new concepts in circuit architecture. Small size, light weight, low power, durability, and reliability were key considerations in the design of the instrument. The primary purpose of the instrument was for collecting VLF data during ground surveys over small grid areas.