Results 251 to 260 of about 6,346,538 (309)

An Advanced Nonlinear Frequency Modulation Waveform for Radar Imaging With Low Sidelobe

IEEE Transactions on Geoscience and Remote Sensing, 2019
With the development of high-resolution radar satellite for global comprehensive environmental monitoring, day-and-night and all-weather surveillance has become an active and growing research field. However, in all cases, these applications require radar
Guodong Jin, Yunkai Deng, Robert Wang, Wei Wang, Pei Wang, Yajun Long, Zhi Zhang, Yongwei Zhang   +7 more
semanticscholar   +1 more source

Nonlinear Frequency Modulation Signal Generator in LT-1

IEEE Geoscience and Remote Sensing Letters, 2019
Generally, synthetic aperture radar (SAR) system transmits linear frequency modulation (LFM) signal to obtain the high-resolution image and weighted windowing is usually employed to suppress sidelobes.
Guodong Jin, Kaiyu Liu, Yunkai Deng, Y. Sha, Robert Wang, Dacheng Liu, Wen Wang, Yajun Long, Yongwei Zhang   +8 more
semanticscholar   +1 more source

Experimental study on the intrawave frequency modulation characteristic of rotor rub and crack fault

Mechanical systems and signal processing, 2019
Rub and crack are two important rotor faults. In this paper, the rub, crack and rub-crack coupled fault experiments are performed on a rotor test rig and the instantaneous frequency signatures of the faults are analyzed using Hilbert–Huang transform. The
Aijun Hu, Ling Xiang, Yue Zhang
semanticscholar   +1 more source

A Novel Dual Switching Frequency Modulation for Z-Source and Quasi-Z-Source Inverters

IEEE transactions on industrial electronics (1982. Print), 2018
Impedance network inverters are the best alternatives for voltage-source and current-source inverters. The boosting capability and the shoot-through solution of such converters make them excellent solutions for various applications.
M. Mohammadi, J. Moghani, J. Milimonfared   +2 more
semanticscholar   +1 more source

Automatic determination of digital modulation types with different noises using Convolutional Neural Network based on time-frequency information

Applied Soft Computing, 2020
In this study, a novel digital modulation classification model has been proposed for automatically recognizing six different modulation types including amplitude shift keying (ASK), frequency shift keying (FSK), phase-shift keying (PSK), quadrate ...
N. Daldal, Zafer Cömert, K. Polat
semanticscholar   +1 more source

Generalized tamed frequency modulation

ICASSP '82. IEEE International Conference on Acoustics, Speech, and Signal Processing, 2005
Continued investigation of Tamed FM (TFM) has led to an extension, called Generalized Tamed FM (GTFM). The features of GTFM are based on the possibility to select different combinations of parameters which characterize the process of waveform generation.
Kah-Seng Chung, Leo E. Zegers
openaire   +1 more source

Frequency modulation of transmitter release

Journal of Physiology-Paris, 1993
In 1952 Fatt and Katz recorded at a frog neuromuscular junction while stimulating the nerve and found "... that successive endplate potential responses varied in a step-like manner, corresponding to units of miniature endplate potentials" (J Physiol 117, 109-128). This led them to propose that fast neuromuscular transmission is 'quantal'.
J, Vautrin, A E, Schaffner, B, Fontas, J L, Barker   +3 more
openaire   +2 more sources

Frequency-modulation-polarization spectroscopy

Optics Letters, 1983
We have combined frequency-modulation and polarization spectroscopy to detect anisotropic spectral features with high sensitivity. The many line shapes possible with this technique and the potential for laser noise suppression were demonstrated by using saturation holes in iodine vapor.
M, Romagnoli, M D, Levenson, G C, Bjorklund   +2 more
openaire   +2 more sources

Layered Orthogonal Frequency Division Multiplexing With Index Modulation

IEEE Systems Journal, 2019
In this paper, we propose a novel scheme termed layered orthogonal frequency division multiplexing with index modulation (L-OFDM-IM) to increase the spectral efficiency (SE) of OFDM-IM systems.
Jun Li, Shuping Dang, Miaowen Wen, Xueqin Jiang, Yuyang Peng, Han Hai   +5 more
semanticscholar   +1 more source

Low frequency photoelastic modulator

Applied Optics, 1984
In this paper, we propose a new excitation mode of a photoelastic modulator previously shown to perform low frequency polarization modulation. Photoacoustic and photothermal polarization spectroscopy is possible with this modulation scheme which has the specific advantages of large light throughput and freedom from mechanical vibrations.
J C, Canit, C, Pichon
openaire   +2 more sources