Topic
Pulse-frequency modulation
About: Pulse-frequency modulation is a research topic. Over the lifetime, 4151 publications have been published within this topic receiving 53039 citations. The topic is also known as: PFM.
Papers published on a yearly basis
Papers
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06 Oct 2003
TL;DR: In this paper, the interference effect between the signal lights and the optical pulses is considered, which is a linear correlation between the signals and optical pulses, so that it suffices for both the signal light and the pulses to have relatively low intensities, and the reception sensitivity is high.
Abstract: The optical sampling system realizes the optical sampling by detecting the interference effect which is a linear correlation between the signal lights and the optical pulses, so that it suffices for both the signal lights and the optical pulses to have relatively low intensities, and the reception sensitivity is high. Also, the pulse width of the optical pulses and the amount of delay given to the optical pulses are the only factors that limit the time resolution, so that it is possible to provide the optical sampling system with excellent time resolution and power consumption properties, and it is possible for the optical sampling system to monitor not only the intensity of the signal lights but also the frequency modulation component as well.
12 citations
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18 Dec 2014
12 citations
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04 Oct 2006TL;DR: A novel dithering skip modulation (DSM) is introduced to smooth the efficiency curve and can dynamically skip the number of gate driving pulses, which is inverse proportional to load current.
Abstract: Dithering skip mode with a novel load sensor for DC-DC converters is proposed to maintain a high efficiency over a wide load range. Due to the efficiency drop of the transition from the pulse-width modulation (PWM) to pulse-frequency modulation (PFM), a novel dithering skip modulation (DSM) is introduced to smooth the efficiency curve. Importantly, DSM mode can dynamically skip the number of gate driving pulses, which is inverse proportional to load current. Besides, a novel proposed load sensor can automatically select the optimum modulation method from these three modulation methods without an external selection pin. Simulation results shows DSM can maintain the efficiency of converters as high as about 89% over a wide load current range from 3mA to 500mA.
12 citations
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06 Nov 2008TL;DR: In this article, a two-mode beat light source and an optical intensity modulator are used to generate a CS optical pulse train, which is then modulated by the second electric modulation signal.
Abstract: The device is structured to have a first electric modulation signal generator, a second electric modulation signal generator, a two-mode beat light source and an optical intensity modulator. The first electric modulation signal generator generates and outputs a first electric modulation signal. The second electric modulation signal generator generates and outputs a second electric modulation signal of a same frequency as the first electric modulation signal and to which a phase difference of δ radians is provided (δ is a real number satisfying 0≦δ≦π). The two-mode beat light source is driven by the first electric modulation signal, and generates and outputs two-mode beat light. The two-mode beat light is inputted to the optical intensity modulator, and the optical intensity modulator generates and outputs a CS optical pulse train. Light transmittance of the optical intensity modulator is modulated by the second electric modulation signal.
12 citations
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12 Jun 2006TL;DR: In this article, a modulator including a direct modulation synthesizer circuit, a reference frequency oscillator for providing an input reference signal to the direct modulation synthesis circuit for locking a carrier frequency to a stable frequency and a pre-emphasis unit for data bits is presented.
Abstract: A modulator including a direct modulation synthesizer circuit, a reference frequency oscillator for providing an input reference signal to the direct modulation synthesizer circuit for locking a carrier frequency to a stable frequency and a pre-emphasis unit for data bits and for producing a modulating signal for direct modulation of the direct modulation synthesizer circuit, the modulating signal having data bit dependent voltage levels.
12 citations