Low-noise amplifier, anti-alias filtered, and then directly sampled by the ADCs. As can be seen, the signal from the antenna is amplified in a A block diagram of a typical ELF/VLF receiver is shown in Figure 1. This allows us to avoid using heterodyning techniques, which reduces complexity and saves power. A direct conversion, or zero IF, radio receiver is almost always used since modern analog-to-digital (ADC) converters are more than capable of sampling sufficiently fast to capture the entire ELF/VLF band without downconversion. These needs necessitate the development of low-power ELF/VLF receivers that are capable of autonomous operation in harsh environments without external power sources.Ī typical ELF/VLF receiver records broadband data over the entire 300Hz-30kHz ELF/VLF band. Many of these studies also require that receivers be deployed in extremely remote, electromagnetically quiet locations such as Antarctica, Alaska, or even the middle of the ocean. Any applied studies of these events, however, require electromagnetic waves in the ELF/VLF band to be amplified, captured, processed, and stored. Naturally occurring ELF/VLF emissions from lightning strikes can be detected for thousands of miles and provide an abundance of wave-particle interaction possibilities in the radiation belts. Naturally occurring ELF/VLF emissions from lightning strikes can be detected for thousands of miles and provide an abundance of wave-particle interaction possibilities in the radiation belts.ĮLF/VLF radio signals, in approximately the 300Hz to 30kHz band, are commonly used for ionospheric remote sensing, geophysical prospecting, and studies of the near-Earth space environment.
In addition to the acquisition of VLF transmitter signals at various frequencies, tweek atmospherics are also clearly captured to occur at multiple modes up to n = 6.ELF/VLF radio signals, in approximately the 300Hz to 30kHz band, are commonly used for ionospheric remote sensing, geophysical prospecting, and studies of the near-Earth space environment. The validity and feasibility of the self-developed ground-based ELF/VLF receiver system is evaluated by first results of experimental data that show the temporal variation of broadband ELF/VLF wave spectral intensity in Wuhan (30.54 °N, 114.37 ☎).
#Elf vlf receiver serial#
On basis of field programmable gate array (FPGA) device and Universal Serial Bus (USB) architecture, the digital receiver is developed along with time keeping and synchronization module. A new structure is adopted in the analog front end to provide high common-mode rejection and to reduce interference. This paper presents the principle and architecture of the system framework, including magnetic loop antenna design, low-noise analog front-end and digital receiver with data sampling and transmission.
These low-frequency radio waves are useful for ionospheric remote sensing, geospace environment monitoring, and submarine communications. A new digital low-frequency receiver system has been developed at Wuhan University for sensitive reception of low-latitude broadband Extremely Low Frequency (ELF) and Very Low Frequency (VLF) radio waves originating from either natural or artificial sources.