Correcting image distortions from a nonlinear B1+$$ {\boldsymbol{B}}_{\mathbf{1}}^{+} $$ ‐gradient field in frequency‐modulated Rabi‐encoded echoes
Sign Up to like & getrecommendations! Published in 2022 at "Magnetic Resonance in Medicine"
DOI: 10.1002/mrm.29549
Abstract: To correct image distortions that result from nonlinear spatial variation in the transmit RF field amplitude ( B1+$$ {B}_1^{+} $$ ) when performing spatial encoding with the method called frequency‐modulated Rabi encoded echoes (FREE). read more here.
Keywords: image distortions; frequency modulated; rabi encoded; encoded echoes ... See more keywords
Detection of Frequency Modulated Signals Using a Robust IF Estimation Algorithm
Sign Up to like & getrecommendations! Published in 2020 at "Circuits, Systems, and Signal Processing"
DOI: 10.1007/s00034-019-01258-z
Abstract: This paper presents a methodology to detect non-stationary frequency modulated signals under noise process uncertainty. The proposed method uses the combination of adaptive directional time–frequency distribution and modified Viterbi algorithm to robustly estimate the instantaneous… read more here.
Keywords: using robust; detection frequency; modulated signals; frequency modulated ... See more keywords
Frequency-modulated continuous-wave laser radar using dual vertical-cavity surface-emitting laser diodes for real-time measurements of distance and radial velocity
Sign Up to like & getrecommendations! Published in 2017 at "Optical Review"
DOI: 10.1007/s10043-016-0294-7
Abstract: A frequency-modulated continuous-wave (FMCW) laser radar capable of real-time displaying the distance to a target object and its radial velocity as their corresponding frequency spectra is developed. The system employs a pair of oppositely frequency-swept… read more here.
Keywords: continuous wave; real time; frequency modulated; frequency ... See more keywords
Mutual interferences in frequency-modulated continuous-wave (FMCW) LiDARs
Sign Up to like & getrecommendations! Published in 2020 at "Optik"
DOI: 10.1016/j.ijleo.2020.165109
Abstract: Abstract This paper investigates mutual interferences between FMCW LiDARs both experimentally and theoretically. We show that the FMCW LiDARs have mutual interference problems as those of the FMCW radars. The transient interference degrades the signal-to-noise… read more here.
Keywords: frequency modulated; mutual interferences; fmcw lidars; interferences frequency ... See more keywords
Theoretical and experimental study of the light deflection by a frequency modulated ultrasonic wave
Sign Up to like & getrecommendations! Published in 2017 at "Optics and Laser Technology"
DOI: 10.1016/j.optlastec.2017.07.002
Abstract: Abstract A formula that describes angular excursion variation of an acousto-optical deflector is theoretically demonstrated and experimentally confirmed. This deflector is obtained using a laser beam interaction with a frequency modulated ultrasonic sinusoidal wave in… read more here.
Keywords: frequency modulated; frequency; theoretical experimental; angular excursion ... See more keywords
Auditory identification of frequency-modulated sweeps and reading difficulties in Chinese.
Sign Up to like & getrecommendations! Published in 2019 at "Research in developmental disabilities"
DOI: 10.1016/j.ridd.2019.01.006
Abstract: BACKGROUND In Chinese Mandarin, lexical tones play an important role of providing contrasts in word meaning. They are pitch patterns expressed by frequency-modulated (FM) signals. Yet, few studies have looked at the relationship between low-level… read more here.
Keywords: frequency processing; frequency modulated; frequency; auditory frequency ... See more keywords
Historical surface mass balance from a frequency-modulated continuous-wave (FMCW) radar survey from Zhongshan station to Dome A
Sign Up to like & getrecommendations! Published in 2020 at "Journal of Glaciology"
DOI: 10.1017/jog.2020.58
Abstract: Abstract Using frequency-modulated continuous wave radar data from the 32nd Chinese Antarctic Research Expedition in 2015/16, subsurface profiles were obtained along an East Antarctic inland traverse from Zhongshan station to Dome A, and four distinct… read more here.
Keywords: continuous wave; smb; frequency modulated; radar ... See more keywords
Stochastic resonance induced by an unknown linear frequency modulated signal in a strong noise background.
Sign Up to like & getrecommendations! Published in 2020 at "Chaos"
DOI: 10.1063/5.0002134
Abstract: Stochastic resonance (SR) is widely used as a signal enhancement technique in recovering and enhancing periodic or aperiodic signals submerged in noise. However, system parameters and noise intensity tend to influence the SR performance. To… read more here.
Keywords: frequency modulated; resonance; stochastic resonance; lfm signal ... See more keywords
Atmospheric visibility correlates with photon travel time delay from frequency modulated continuous-wave Doppler wind lidar
Sign Up to like & getrecommendations! Published in 2023 at "International Journal of Remote Sensing"
DOI: 10.1080/01431161.2023.2214273
Abstract: ABSTRACT Atmospheric visibility, or meteorological optical range (MOR), is governed by light extinction by aerosols and is linked to air quality and Earth’s climate. A coherent frequency modulated continuous wave (FMCW) Doppler wind lidar has… read more here.
Keywords: atmospheric visibility; frequency modulated; modulated continuous; continuous wave ... See more keywords
Multiple Targets Detection of Linear Frequency-Modulated Continuous Wave Active Sonar Using Fractional Fourier Transform
Sign Up to like & getrecommendations! Published in 2020 at "Integrated Ferroelectrics"
DOI: 10.1080/10584587.2020.1728798
Abstract: Abstract In order to improve the detection performance of active sonar and make up for the shortcomings of pulsed active sonar (PAS), linear frequency-modulated continuous wave (LFMCW) was applied in continuous active sonar (CAS). The… read more here.
Keywords: frequency modulated; sonar; linear frequency; modulated continuous ... See more keywords
Simultaneous range ambiguity mitigation and sidelobe reduction using orthogonal non-linear frequency modulated (ONLFM) signals for satellite SAR Imaging
Sign Up to like & getrecommendations! Published in 2018 at "Remote Sensing Letters"
DOI: 10.1080/2150704x.2018.1486518
Abstract: ABSTRACT This letter first attempts to simultaneously reduce range ambiguities and sidelobes in spaceborne synthetic aperture radar (SAR). Two of the limitations of SAR are the range ambiguity phenomenon and the sidelobes effect. The range… read more here.
Keywords: frequency modulated; linear frequency; range ambiguity; range ... See more keywords