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Frequency Shift Chirp Modulation: The LoRa Modulation
IEEE Signal Processing Letters, 2017Low power wide area networks (LPWAN) are emerging as a new paradigm, especially in the field of Internet of Things (IoT) connectivity. LoRa is one of the LPWAN and it is gaining quite a lot of commercial traction. The modulation underlying LoRa is patented and has never been described theoretically.
Lorenzo Vangelista
exaly +4 more sources
Psychoacoustic equivalence of frequency modulation and quasi-frequency modulation
The Journal of the Acoustical Society of America, 1994Frequency modulation (FM) is known to be reasonably approximated by quasi-frequency modulation (QFM) for small modulation indices, β, but the range of β for which this approximation is appropriate is unclear. Thresholds for discrimination between FM and QFM with equal β’s are obtained in order to estimate an upper bound on β for determining when this ...
B W, Edwards, N F, Viemeister
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Theory of frequency modulation detection for low modulation frequencies
The Journal of the Acoustical Society of America, 1980There is general agreement that the frequency difference limen measured in a two-sine-tone frequency discrimination experiment is smaller than that measured in a frequency modulation (FM) experiment. We present a model of frequency modulation detection for low modulation frequencies, within the framework of signal detection theory, which accounts well ...
Hartmann, W. M., Klein, M. A.
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Research of frequency modulation to amplitude modulation with multi-frequency modulation
SPIE Proceedings, 2013ABSTRACT For better performance of laser coupling in inertial confinement fusion (ICF), beam shaping of the focus spot is required. Among all the beam smoothing methods, the multi frequency modulation smoothing by spectral dispersion (MultiFM-SSD) proposed by LLE has the advantages of the faster smoothing and better operability.
Yuliang Zhou +5 more
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Frequency Modulation and the Difference Limen for Frequency
The Journal of the Acoustical Society of America, 1969A system for tracking difference limen for frequency (ΔF) is described. The system uses a function generator to frequency modulate a BFO. The amplitude of the modulating voltage is controlled by a recording attenuator. Intuitive spectral analysis of the modulated tone proves to be insufficient and correction factors are given to allow determination of ...
L L, Feth, R V, Wolf, R C, Bilger
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IEEE Transactions on Communications, 1983
One modulation method called the frequency counting modulator (FCM), which can produce various constant envelope signals, is proposed. The FCM is materialized by only digital circuits and, therefore, is easily implemented in a large scale integrated circuit (LSI).
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One modulation method called the frequency counting modulator (FCM), which can produce various constant envelope signals, is proposed. The FCM is materialized by only digital circuits and, therefore, is easily implemented in a large scale integrated circuit (LSI).
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Applied Optics, 1988
We discuss two methods (Zeeman modulation and Doppler modulation) for locking the frequency of a singlemode cw laser to an atomic absorption line. These methods do not require the laser frequency to be modulated directly. In the first scheme the absorption frequency of the atom is modulated via the Zeeman effect; in the second scheme the laser ...
A, Weis, S, Derler
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We discuss two methods (Zeeman modulation and Doppler modulation) for locking the frequency of a singlemode cw laser to an atomic absorption line. These methods do not require the laser frequency to be modulated directly. In the first scheme the absorption frequency of the atom is modulated via the Zeeman effect; in the second scheme the laser ...
A, Weis, S, Derler
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Applied Optics, 2009
Frequency modulation to amplitude modulation (FM-to-AM) conversion is an important issue that can prevent fusion ignition with high power lasers such as the Laser MegaJoule (LMJ). On LMJ, most of the FM-to-AM conversion is expected in the so-called frequency conversion and focusing system, which is a nonlinear system.
Steve, Hocquet +2 more
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Frequency modulation to amplitude modulation (FM-to-AM) conversion is an important issue that can prevent fusion ignition with high power lasers such as the Laser MegaJoule (LMJ). On LMJ, most of the FM-to-AM conversion is expected in the so-called frequency conversion and focusing system, which is a nonlinear system.
Steve, Hocquet +2 more
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Frequency Modulation and The Human Ear
Acta Oto-Laryngologica, 1957(1957). Frequency Modulation and The Human Ear. Acta Oto-Laryngologica: Vol. 47, No. 5, pp. 421-430.
J J, GROEN, R M, VERSTEEGH
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Coded Phase/Frequency Modulation
IEEE Transactions on Communications, 1986Channel coding combined with expanded signal sets has been shown [1] to improve error performance over uncoded modulation without expanding the bandwidth of the transmitted signals. In this paper, new coded modulation formats defined over an expanded set of signals varying both in phase and frequency are presented.
Roberto Padovani, Jack Keil Wolf
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