#Tunable vlf receiver full#
Users should refer to the original published version of the material for the full abstract. The standard VLF data form was a sonogram (graph) showing signals as a. The receiver output, which sensed the electric field component of the signal strength, was maintained constant by means of an AGC loop.
No warranty is given about the accuracy of the copy. This experiment was a wideband high-gain receiver with a passband from 0.4 to 10 kHz using only the longest (45.7 m) sounder antenna. a balloonborne tunable diode laser spectrometer devoted to the in situ. However, users may print, download, or email articles for individual use. VLF receivers must selectively filter out unwanted emissions and amplify the. The VLF and LF bands have their own unique useful characteristics and these will be discussed further on.
Copyright of International Journal of Antennas & Propagation is the property of Hindawi Limited and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. It has been designated a VLF-LF receiver, because it tunes the VLF-LF range from 10 to 300 kHz, but it also tunes part of the MF spectrum from 300 to 500 kHz.The noise and received signal-to-noise ratio (SNR) of the matching network were assessed to find that, with a low noise floor level (4 dB) receiver, the SNR of the passive loaded antenna performs better than the non-Foster loaded antenna in VLF. A loop antenna was matched to the designed NFC with −10 dB S11 fractional bandwidth, marking a 383% improvement as well as enhanced transducer gain (S21) compared to most bands in passive matching (over 15–30 kHz). The NFC can be applied to different VLF loop antennas by adjusting the number and inductance of the cells in the tunable inductor. The ultra-low-power ELF/VLF receiver system will provide the same functionality at a power level of 10 mW, while eliminating the need for the preamp, and the cable, and reducing the physical size of the main receiver unit to a housing as large as a small paperback book, and allowing for substantial enhanced flexibility (e.g., bandwidth and.
The receiver basically is a tunable audio frequency amplifier with an envelope detector. A 1 ⁎ 1 m VLF receive loop antenna was designed with a CMOS switch-based tunable inductor built into the NFC. VLF Whistler Reception US Navy LF & VLF Receivers - 1950s. Abstract: This paper presents a non-Foster matching circuit (NFC) for very low frequency (VLF) receive loop antennas.