Dual-antenna GNSS spoofing detection method based on Doppler frequency difference of arrival
Sign Up to like & getrecommendations! Published in 2019 at "GPS Solutions"
DOI: 10.1007/s10291-019-0868-5
Abstract: Recent years have witnessed the emergence of portable global navigation satellite spoofing devices. A variety of anti-spoofing techniques have been dedicated to detecting the presence of spoofing signals, most of which solely utilize either signal… read more here.
Keywords: detection; gnss; dual antenna; method ... See more keywords
Detecting embedded rebar in cement mortar by frequency-difference electrical resistance tomography
Sign Up to like & getrecommendations! Published in 2021 at "Automation in Construction"
DOI: 10.1016/j.autcon.2021.103974
Abstract: Abstract This study investigated frequency-difference electrical resistance tomography (ERT) using a 16-channel ERT system to detect rebar embedded in cement mortar. Two different data collecting methods (i.e., reference-difference and frequency-difference) were used for ERT image… read more here.
Keywords: rebar; difference; frequency difference; cement mortar ... See more keywords
Dual-frequency light source with widely tunable frequency difference based on single-side-band modulator
Sign Up to like & getrecommendations! Published in 2019 at "Optics Communications"
DOI: 10.1016/j.optcom.2019.03.067
Abstract: Abstract A dual-frequency light source at 1550 nm with widely tunable frequency difference is proposed and experimentally demonstrated. Two beams are split from the same single-frequency source and then modulated by two parallel single-side-band (SSB) modulators… read more here.
Keywords: frequency difference; frequency light; light source; frequency ... See more keywords
Radially polarized terahertz (THz) generation by frequency difference of Hermite Cosh Gaussian lasers in hot electron-collisional plasma
Sign Up to like & getrecommendations! Published in 2020 at "Optics and Lasers in Engineering"
DOI: 10.1016/j.optlaseng.2020.106257
Abstract: Abstract We report a scheme to generate radially polarized THz radiation by frequency difference of Hermite Cosh Gaussian lasers in hot electron, collisional and density modulated plasma. The effect of laser (spatial field distribution) and… read more here.
Keywords: plasma; field; radially polarized; thz ... See more keywords
Dark hollow lasers may be better candidates for holography
Sign Up to like & getrecommendations! Published in 2020 at "Optics and Laser Technology"
DOI: 10.1016/j.optlastec.2020.106485
Abstract: Abstract Gaussian laser beams have been very successful in various fields including holography where two lasers with frequency difference have been used, but good quality holograms could be produced only for small frequency detuning. The… read more here.
Keywords: dark hollow; may better; lasers may; hollow lasers ... See more keywords
Frequency Difference EIT With Localization: A Potential Medical Imaging Tool During Cancer Treatment
Sign Up to like & getrecommendations! Published in 2019 at "IEEE Access"
DOI: 10.1109/access.2019.2898091
Abstract: Electrical impedance tomography (EIT) has attracted great interest in a number of medical applications. It offers several unique advantages, such as being safe, low cost, and having high temporal resolution over other tomographic imaging protocols.… read more here.
Keywords: frequency difference; resolution; frequency; medical imaging ... See more keywords
Dual-frequency solid-state microchip laser and its frequency difference control
Sign Up to like & getrecommendations! Published in 2019 at "Optical Engineering"
DOI: 10.1117/1.oe.58.11.116105
Abstract: Abstract. Dual-frequency solid-state microchip lasers have advantages, such as large frequency differences, high pumping efficiency, high beam quality, and narrow laser linewidth. In addition, they are characterized by simplicity, compactness, stability, long lifetime, etc. However,… read more here.
Keywords: frequency difference; frequency; microchip; dual frequency ... See more keywords
Frequency difference stabilization in Y-shaped cavity dual-frequency laser with the aid of precision passive control
Sign Up to like & getrecommendations! Published in 2021 at "Optical Engineering"
DOI: 10.1117/1.oe.60.3.034107
Abstract: Abstract. We present a precise passive frequency difference stabilization scheme for the Y-shaped cavity dual-frequency laser. A two-stage thermostat and a precision steady current circuit were designed to stabilize the temperature and discharge current of… read more here.
Keywords: frequency difference; difference stabilization; frequency; laser ... See more keywords
Simulations of source localization in the deep ocean using frequency-difference matched field processing
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DOI: 10.1121/1.4988825
Abstract: Matched field processing (MFP) is an established technique for source localization in multi-path acoustic environments that relies on correlating array-recorded and simulated sound fields. However, when the recorded sound field’s frequency is high enough, this… read more here.
Keywords: deep ocean; frequency; field; source ... See more keywords
Cross-term analysis in frequency-difference-based source localization methods
Sign Up to like & getrecommendations! Published in 2018 at "Journal of the Acoustical Society of America"
DOI: 10.1121/1.5036416
Abstract: In previous work, it has been shown that a quadratic product of frequency-domain acoustic fields at different frequencies but the same spatial location leads to an auxiliary field which may contain field information at frequencies… read more here.
Keywords: frequency; frequency difference; source localization;