Journal articles: 'Pulse Density Modulation'

1

Yamaji, T. "Vector pulse-density modulation." Electronics Letters 30, no. 20 (September 29, 1994): 1652–53. http://dx.doi.org/10.1049/el:19941134.

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Eschbach, Reiner. "Pulse-density modulation on rastered media: combining pulse-density modulation and error diffusion." Journal of the Optical Society of America A 7, no. 4 (April 1, 1990): 708. http://dx.doi.org/10.1364/josaa.7.000708.

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Maron, O., M. Serylak, J. Kijak, K. Krzeszowski, D. Mitra, and A. Jessner. "Pulse-to-pulse flux density modulation from pulsars at 8.35 GHz." Astronomy & Astrophysics 555 (June 24, 2013): A28. http://dx.doi.org/10.1051/0004-6361/201220698.

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Eschbach, R., and R. Hauck. "Binarization using a two-dimensional pulse-density modulation." Journal of the Optical Society of America A 4, no. 10 (October 1, 1987): 1873. http://dx.doi.org/10.1364/josaa.4.001873.

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Oncu, Selim, and Akif Karafil. "Pulse density modulation controlled converter for PV systems." International Journal of Hydrogen Energy 42, no. 28 (July 2017): 17823–30. http://dx.doi.org/10.1016/j.ijhydene.2017.05.163.

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Wiatrowski, A., and W. M. Posadowski. "The impact of medium frequency pulsed magnetron discharge power on the single probe Langmuir measurements and resulted plasma parameters." Materials Science-Poland 34, no. 2 (June 1, 2016): 374–85. http://dx.doi.org/10.1515/msp-2016-0012.

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AbstractThe resonant type power supplies of medium frequency designed for magnetron sputtering processes often use pulse density modulation to regulate the average discharge power level. While the output power level changes then number of pulses in a group changes, but the discharge current pulses are the same from pulse to pulse: their parameters (duration time, amplitude) do not change with the discharge power. The goal of this paper is to present the influence of medium frequency discharge power level on the direct current I-V characteristics of a single Langmuir probe and resulting plasma parameters caused by the pulse density modulation. The sputtering processes of titanium and copper were diagnosed at two spatial positions. The measured Langmuir probe I-V characteristics showed strong dependence on the discharge power. As the discharge powering pulses stay the same with the discharge power level change, such influence was unlikely to occur. Using time-resolved analysis of probe current waveforms the origin of this influence was indicated. The influence of discharge power level on the single probe Langmuir I-V characteristics and resulting plasma parameters was eliminated using a simple method of scaling the results. Finally, the reliable plasma parameters were calculated.

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Lu, Zhi Bin, Yong Long Peng, and Ya Bin Li. "A New PDM Power Control Technology for the Resonant Inverter." Advanced Materials Research 744 (August 2013): 552–55. http://dx.doi.org/10.4028/www.scientific.net/amr.744.552.

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Pulse density modulation (PDM) can be used to regulate the output power of the resonant converter. However, in some case of low Q value, the output current is discontinuous and unstable in light load condition which is regulated by PDM. In order to solve this problem, a new Hybrid Pulse Density Modulation method is proposed. The principle of the Hybrid Pulse Density Modulation technique and the control method are analyzed in detail. Through experiments, it is proven that this method not only has the advantages of symmetrical control pulse distribution, smooth and continuous output current, simple control. It also achieves modular design, we can adjust the levels of the inverters output power flexibly through change the number of the basic control module.

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Wojtkowski, Wojciech, and Rafał Kociszewski. "Stochastic pulse density modulation for a power LED driver." Photonics Letters of Poland 12, no. 2 (July 1, 2020): 64. http://dx.doi.org/10.4302/plp.v12i2.1027.

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PWM signals are widely used and are easy to implement in a variety of LEDs applications, however they suffer from significant harmonic generation. As an alternative, SPDM - Stochastic Pulse Density Modulation or SSDM – Stochastic Signal Density Modulation ideas may be considered. The SPDM idea is to spread the energy at different frequencies so that it is easier to filter the desired harmonics, because of their lower amplitudes. Example of implementation of SPDM in LED application using a programmable system-on-chip device is presented in the paper. Proper operation of the proposed implementation is proved by the laboratory results. Full Text: PDF ReferencesW. Wojtkowski, A. Karpiuk, The Influence of the PWM frequency and duty cycle of a RGB LED driver on the optical spectrum of the emitted light, Przeglad Elektrotechniczny, 2012, R. 88, nr 4a, pp. 217-219. CrossRef J. Hegedüs, G. Hantos, A. Poppe, Light output stabilisation of LED based streetlighting luminaires by adaptive current control, Microelectronics Reliability, vol. 79, pp. 448-456, 2017. CrossRef J. Kusznier, W. Wojtkowski, Spectral properties of smart LED lamps, PHOTONICS LETTERS OF POLAND, VOL. 12 (1), 16-18 (2020) CrossRef I. Fryc, P. Tabaka, "Zanieczyszczenia nocnego nieboskłonu światłem emitowanym przez oprawy oświetlenia zewnętrznego", Przeglad Elektrotechniczny R93(6), 46 (2017). DirectLink I. Fryc, F. Bisegna, P. Tabaka, Lighting of recreation grounds as a source of sky glow - the influence of luminaire type on this phenomenon, 1st IEEE International Conference On Environment And Electrical Engineering and 17th IEEE Industrial And Commercial Power Systems Europe (2017). CrossRef M. Gilewski, "The ecological hazard of artificial lighting in greenhouses", Photon. Lett. Poland 11(3), 87 (2019). CrossRef J. Kusznier, W. Wojtkowski, Impact of climatic conditions on PV panels operation in a photovoltaic power plant, IEEE, 2019 15th Selected Issues of Electrical Engineering and Electronics (WZEE), Zakopane, Poland (2019). CrossRef J. Kusznier, W. Wojtkowski, Impact of climatic conditions and solar exposure on the aging of PV panels, IEEE, 2019 15th Selected Issues of Electrical Engineering and Electronics (WZEE), Zakopane, Poland (2019). CrossRef PSoC® Technical Reference Manual - Document No. 001-14463 Rev. *K. Cypress Semiconductor Corp. 2017. DirectLink

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Rohit, Shinde, Ramachandiran Gunabalan, and Mehtra Pavan Kumar. "Pulse Density Modulation Flyback Converter for LED Automotive Lighting." Indonesian Journal of Electrical Engineering and Computer Science 8, no. 1 (October 1, 2017): 85. http://dx.doi.org/10.11591/ijeecs.v8.i1.pp85-91.

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Switched mode power supply (SMPS) converter is a dc-dc power electronic converter which is used to step up or step down the dc output voltage. A dimmable driver circuit for Light Emitting Diode (LED) lamp for automotive lighting with dimming feature is used in this paper. A flyback converter is used as a driver circuit operated in discontinuous conduction mode to perform dimming control of LEDs. High overall circuit efficiency is achieved by regulating the current through the LED lamps using pulse density modulation scheme. The LED driver circuit design and operating principle is discussed in detail. A gentle current control feature is achieved by pulse density modulation technique. The high performance driver circuit is designed for 25 W LED lamps.

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10

Nieznański, J. "Analytical establishment of the minimum-distortion pulse density modulation." Electrical Engineering 80, no. 4 (August 1997): 251–58. http://dx.doi.org/10.1007/bf01232797.

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Ikeda, Yoshitaka, Rokusaburo Sakai, Kazuaki Asano, and Takayuki Sakamoto. "Three Phase VVVF Power Inverter Using Resonant Pulse Density Modulation." IEEJ Transactions on Industry Applications 115, no. 4 (1995): 379–86. http://dx.doi.org/10.1541/ieejias.115.379.

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Gupta, Mahima, and Giri Venkataramanan. "Smart-Switching Pulse Width Modulation for High-Density Power Conversion." IEEJ Journal of Industry Applications 9, no. 3 (May 1, 2020): 282–90. http://dx.doi.org/10.1541/ieejjia.9.282.

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Eguchi, Hirotoshi, Toshiyuki Furuta, Hiroyuki Horiguchi, and Sugitaka Oteki. "Neural network hardware with learning function using pulse-density modulation." Electronics and Communications in Japan (Part II: Electronics) 74, no. 11 (1991): 66–75. http://dx.doi.org/10.1002/ecjb.4420741108.

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Eschbach, R., and R. Hauck. "A 2-D pulse density modulation by iteration for halftoning." Optics Communications 62, no. 5 (June 1987): 300–304. http://dx.doi.org/10.1016/0030-4018(87)90294-x.

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Tomberg, Jouni, and Kimmo Kaski. "SOME IC IMPLEMENTATIONS OF ARTIFICIAL NEURAL NETWORKS USING SYNCHRONOUS PULSE-DENSITY MODULATION TECHNIQUE." International Journal of Neural Systems 02, no. 01n02 (January 1991): 101–14. http://dx.doi.org/10.1142/s0129065791000091.

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Pulse-density modulation technique offers a very effective and robust method to implement artificial neural network structures, because it mimics some biological features of neuron action. In this paper various Integrated Circuit (IC) implementations based on the pulse-density modulation technique are explored. Two different approaches has been used: analog switched-capacitor structures and fully digital structures. These structures can be used in both Hopfield-type networks and more complicated Boltzmann-machine as well as other algorithms.

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Sayed, Khairy, and Mutsuo Nakaoka. "Performance of Induction Heating Power Supply Using Dual Control Mode Pulse-width Modulation–Pulse-density Modulation High-frequency Inverter." Electric Power Components and Systems 43, no. 2 (December 31, 2014): 157–66. http://dx.doi.org/10.1080/15325008.2014.975386.

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BOSCOLO, M., M. FERRARIO, C. VACCAREZZA, I. BOSCOLO, F. CASTELLI, and S. CIALDI. "A TRAIN OF MICRO-BUNCHES FOR PWFA EXPERIMENTS PRODUCED BY RF PHOTOINJECTORS." International Journal of Modern Physics B 21, no. 03n04 (February 10, 2007): 415–21. http://dx.doi.org/10.1142/s0217979207042197.

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An electron beam generated in a radio-frequency photo-injector illuminated by a laser "comb" pulse evolves towards a homogenous electron beam with an energy modulation. The density modulation in fact is transformed into an energy modulation, with a saw-tooth like shape, by the longitudinal space charge forces. Such an energy distribution can be exploited to restore the initial density profile by means of a RF accelerating structure operating in the velocity bunching mode. It results a train of short electron bunches suitable for advanced PWFA experiments. The initial laser comb can be obtained with a pulse shaping device inserted into the laser system. In this paper we discuss the beam dynamics features of such a beam.

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Wang, Shengpei, Yoshihiro Konishi, Oleg Koudriavtsev, and Mutsuo Nakaoka. "Voltage-Fed Pulse Density and Pulse Width Modulation Resonant Inverter for Silent Discharge Type Ozonizer." IEEJ Transactions on Industry Applications 120, no. 4 (2000): 587–92. http://dx.doi.org/10.1541/ieejias.120.587.

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Kikombo, Andrew Kilinga, Tetsuya Asai, Takahide Oya, Alexandre Schmid, and Yusuf Leblebici. "A Neuromorphic Single-Electron Circuit for Noise-Shaping Pulse-Density Modulation." International Journal of Nanotechnology and Molecular Computation 1, no. 2 (April 2009): 80–92. http://dx.doi.org/10.4018/jnmc.2009040106.

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Rubavathy, S. Jaanaa, and P. Murugesan. "Pulse Density Modulation Based Series Resonant Inverter Fed Induction Heater System." International Journal of Power Electronics and Drive Systems (IJPEDS) 9, no. 2 (June 1, 2018): 690. http://dx.doi.org/10.11591/ijpeds.v9.i2.pp690-697.

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This paper deals with implementation of a multi-output Series Resonant Inverter(SRI) for induction heating applications, which uses pulse density modulation(PDM) control for full bridge Series resonant inverters for output voltage and power control. It ensures better efficiency performances than conventional control strategies. The proposed converter can be considered as a two output extension of a full bridge inverter. This full bridge inverter can control the two outputs, simultaneously and independently, up to their rated powers, which reduces the usage of number of components as compared with conventional method. It also ensures higher utilization of switches used for its operation. A two output full bridge series resonant inverter is simulated and implemented. The Experimental results are compared with the simulation results.

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Tomberg, J. E., and K. K. K. Kaski. "Pulse-density modulation technique in VLSI implementations of neural network algorithms." IEEE Journal of Solid-State Circuits 25, no. 5 (1990): 1277–86. http://dx.doi.org/10.1109/4.62152.

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Liu, Weihang, Chao Feng, Yi Jiao, and Sheng Wang. "A coherent harmonic generation method for producing femtosecond coherent radiation in a laser plasma accelerator based light source." Journal of Synchrotron Radiation 28, no. 3 (March 22, 2021): 669–80. http://dx.doi.org/10.1107/s1600577521002745.

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The electron beam generated in laser plasma accelerators (LPAs) has two main initial weaknesses – a large beam divergence (up to a few milliradians) and a few percent level energy spread. They reduce the beam brightness and worsen the coherence of the LPA-based light source. To achieve fully coherent radiation, several methods have been proposed for generating strong microbunching on LPA beams. In these methods, a seed laser is used to induce an angular modulation into the electron beam, and the angular modulation is converted into a strong density modulation through a beamline with nonzero longitudinal position and transverse angle coupling. In this paper, an alternative method to generate microbunching into the LPA beam by using a seed laser that induces an energy modulation and transverse–longitudinal coupling beamlines that convert the energy modulation into strong density modulation is proposed. Compared with the angular modulation methods, the proposed method can use more than one order of magnitude lower seed laser power to achieve similar radiation performance. Simulations show that with the proposed method a coherent pulse of a few microjoules pulse energy and femtosecond duration can be generated with a typical LPA beam.

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Smponias, Athanasios, Dionisis Stefanatos, and Emmanuel Paspalakis. "Efficient Biexciton Preparation in a Quantum Dot—Metal Nanoparticle System Using On-Off Pulses." Nanomaterials 11, no. 7 (July 19, 2021): 1859. http://dx.doi.org/10.3390/nano11071859.

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We consider a hybrid nanostructure composed by semiconductor quantum dot coupled to a metallic nanoparticle and investigate the efficient creation of biexciton state in the quantum dot, when starting from the ground state and using linearly polarized laser pulses with on-off modulation. With numerical simulations of the coupled system density matrix equations, we show that a simple on-off-on pulse-sequence, previously derived for the case of an isolated quantum dot, can efficiently prepare the biexciton state even in the presence of the nanoparticle, for various interparticle distances and biexciton energy shifts. The pulse durations in the sequence are obtained from the solution of a transcendental equation.

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Utagawa, Akira, Tetsuya Asai, and Yoshihito Amemiya. "High-fidelity pulse density modulation in neuromorphic electric circuits utilizing natural heterogeneity." Nonlinear Theory and Its Applications, IEICE 2, no. 2 (2011): 218–25. http://dx.doi.org/10.1587/nolta.2.218.

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Sheng, Xuerui, and Liming Shi. "An Improved Pulse Density Modulation Strategy Based on Harmonics for ICPT System." IEEE Transactions on Power Electronics 35, no. 7 (July 2020): 6810–19. http://dx.doi.org/10.1109/tpel.2019.2958644.

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Esteve, Vicente, Esteban Sanchis-Kilders, José Jordan, Enrique J. Dede, César Cases, Enrique Maset, Juan B. Ejea, and Agustín Ferreres. "Improving the Efficiency of IGBT Series-Resonant Inverters Using Pulse Density Modulation." IEEE Transactions on Industrial Electronics 58, no. 3 (March 2011): 979–87. http://dx.doi.org/10.1109/tie.2010.2049706.

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Jacob, B., and M. R. Baiju. "Spread spectrum modulation scheme for two-level inverter using vector quantised space vector-based pulse density modulation." IET Electric Power Applications 5, no. 7 (2011): 589. http://dx.doi.org/10.1049/iet-epa.2010.0260.

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Ke, Shih Tsung, Jeou Long Lee, Yih Min Yeh, Shuo Jen Lee, and Ming Der Ger. "A Study of the Microstructure and Properties of Electroformed Ni-P Model Insert." Key Engineering Materials 364-366 (December 2007): 232–36. http://dx.doi.org/10.4028/www.scientific.net/kem.364-366.232.

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In this study, a Ni-P alloy electroforming nanostructure material with low surface roughness and low internal stress was developed by using a pulse current. Square-wave cathodic current modulation was employed to electrodeposit ultrafine-grained Ni-P films from an additivefree Sulfamate nickel bath. The effect of various factors, such as peak current density, duty cycle and pulse frequency on the roughness and internal stress were investigated. Pulse current significantly influences the microstructure of Ni-P alloys. The internal stress and roughness of Ni-P alloys increased as peak current density increased, but the internal stress of Ni-P alloys decreased as duty cycle decreased.

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Geetha, V., and V. Sivachidambaranathan. "An AC-AC High Frequency Pulse Density Modulated Full Bridge Series Resonant Converter for Induction Heating Application." International Journal of Electrical and Computer Engineering (IJECE) 9, no. 4 (August 1, 2019): 2238. http://dx.doi.org/10.11591/ijece.v9i4.pp2238-2246.

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This paper deals with a new AC – AC single stage full bridge series resonant converter for induction heating application. The proposed system is simulated with high power density modulation technique to produce a output power of 1.8Kw.The main feature of the proposed converter is to reduce the total harmonic distortion produced in the output current for the switching frequency of 29Khz.Asymmetrical pulse density modulation technique is proposed to achieve maximum output power with less harmonic content. It is found that the THD of the proposed high power density modulated converter is 13.43%. Here, the validity of the proposed converter for domestic induction heating application is compared and summarized.

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Li, Hongchang, Jingyang Fang, Shuxin Chen, Kangping Wang, and Yi Tang. "Pulse Density Modulation for Maximum Efficiency Point Tracking of Wireless Power Transfer Systems." IEEE Transactions on Power Electronics 33, no. 6 (June 2018): 5492–501. http://dx.doi.org/10.1109/tpel.2017.2737883.

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Adhikari, Debashis, and C. Bhattacharya. "Analysis of power spectral density of ultra wideband waveforms for pulse shape modulation." International Journal of Ultra Wideband Communications and Systems 3, no. 1 (2014): 19. http://dx.doi.org/10.1504/ijuwbcs.2014.060978.

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Yamada, S., and H. Toshiyoshi. "Self-Powered Artificial Sensory Nervous System Using Ring Oscillator for Pulse Density Modulation." IEEE Electron Device Letters 38, no. 10 (October 2017): 1477–80. http://dx.doi.org/10.1109/led.2017.2742516.

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Utagawa, Akira, Tetsuya Asai, Tetsuya Hirose, and Yoshihito Amemiya. "Noise-shaping pulse-density modulation in inhibitory neural networks with subthreshold neuron circuits." International Congress Series 1301 (July 2007): 71–74. http://dx.doi.org/10.1016/j.ics.2006.12.041.

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Kumar, P. Sharath. "Multiple-load series resonant inverter for induction cooking application with pulse density modulation." Sādhanā 42, no. 8 (June 15, 2017): 1309–16. http://dx.doi.org/10.1007/s12046-017-0651-7.

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Abedi, O., and M. C. E. Yagoub. "Performance Comparison of UWB Pulse Modulation Schemes under White Gaussian Noise Channels." International Journal of Microwave Science and Technology 2012 (October 2, 2012): 1–9. http://dx.doi.org/10.1155/2012/590153.

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In this paper, and for the first time, the performance of various ultra wideband pulse modulation schemes are discussed and compared in terms of narrowband interference robustness, symbol error rate, system complexity, data rate, and maximum transmit power with respect to transceiver distance and channel capacity. The channel model is the UWB IEEE 802.15.3a multipath indoor channel model under additive white Gaussian noise. The transmit power was evaluated by integrating the fifth derivative of the power spectrum density of the Gaussian pulse over the whole bandwidth.

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AFSHARI, VAHID, and CHANGIZ DEHGHANIAN. "THE INFLUENCE OF PULSE PARAMETERS ON THE MICROSTRUCTURE OF IRON ELECTRODEPOSITS." International Journal of Nanoscience 09, no. 04 (August 2010): 365–70. http://dx.doi.org/10.1142/s0219581x10006971.

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Square-wave cathodic current modulation was used to electrodeposit fine-grained iron from citric acid bath. The effect of pulse on-time, off-time, peak current density, and total plating time on the grain size, surface morphology, and crystal orientation was determined. X-ray diffraction analysis and modified Williamson–Hall relation were used to determine the average grains size of the coatings. The experimental results showed that an increase in peak current density resulted in considerable refinement in crystal size of the deposits. An increase in the pulse off-time at constant on-time and peak current density resulted in a progressive increase in crystal size. However, the crystal orientation remained unaffected with increasing off-time. The design of the pulse deposition parameters is described in terms of the transport limitations through the diffusion layer and electrochemical interface stability.

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Booma, Nagarajan, Rama Reddy Sathi, and Vishuram Pradeep. "Comparative Analysis of Various Modulation Strategies for Induction Heating System." Applied Mechanics and Materials 622 (August 2014): 39–43. http://dx.doi.org/10.4028/www.scientific.net/amm.622.39.

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This paper presents a combined asymmetrical voltage cancellation and pulse density modulation technique for energy efficient induction heating system. The proposed technique minimizes the switching losses through soft switching operation and improves the efficiency at low power level. In this modulation technique, the smooth power control can be achieved. The study of power converter has been performed through MATLAB simulation tool and the results are presented. In this proposal, the efficiency of PDM and AVC control techniques are compared with the Hybrid Modulation technique.

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Baruzdin, S. A. "RESOLVING POWER OF MODIFIED IMAGE RECONSTRUCTION METHOD IN SPIN DENSITY PROJECTIONS IN MAGNETIC RESONANCE IMAGING." Journal of the Russian Universities. Radioelectronics, no. 1 (February 28, 2019): 75–83. http://dx.doi.org/10.32603/1993-8985-2019-22-1-75-83.

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The well-known method of image reconstruction by projections in magnetic resonance imaging uses spin echo excited by two sinc pulses. The further processing involves forming of the spin echo signal two quadrature components converting them into a digital format and the subsequent Fourier transform. The proposed modified method is based on the second sinc radio pulse substitution for the linear FM pulse. In this case, the mentioned projections are formed by amplitude detection of the spin echo envelope, which significantly simplifies the processing procedure. The aim of the research is to analyze the modified method resolution. The mathematical model is based on Bloch equations. Their solution is carried out on the basis of the device of the spin system state transition matrices. For their calculation, the stepped approximation of the excitation pulse complex envelopes is used. It makes possible to convert the system of linear differential equations with variable coefficients (Bloch equations) to the system of linear differential equations with piecewise constant coefficients. In this case, the equations have analytical solution. Following the obtained solution, the analysis of the method resolution not previously investigated, is performed by means of modeling the spin echo excitation. The conditions are specified when no dynamic distortions influencing received image quality exist. It is shown that resolution is determined by the size of the scan area, the magnitude of the gradient of the applied magnetic field, the pulse duration with linear frequency modulation, as well as gyromagnetic ratio of the core type used. The developed method eliminates the need for Fourier transform over the spin echo signal and pro-vides resolution comparable to the conventional one.

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AHN, HEE WOOK, and HYUNG GIL JOO MYUNG JOONG YOUN. "Improved pulse density modulation for high-frequency series resonant inverter with transformer-coupled load." International Journal of Electronics 84, no. 1 (January 1998): 69–82. http://dx.doi.org/10.1080/002072198135002.

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Fan, Manyi, Liming Shi, Zhenggang Yin, Longbin Jiang, and Facong Zhang. "Improved Pulse Density Modulation for Semi-bridgeless Active Rectifier in Inductive Power Transfer System." IEEE Transactions on Power Electronics 34, no. 6 (June 2019): 5893–902. http://dx.doi.org/10.1109/tpel.2018.2867902.

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Rogov, Aleksey B. "Smart Arbitrary Waveform Generator with Digital Feedback Control for High-Voltage Electrochemistry." Instruments 3, no. 1 (February 7, 2019): 13. http://dx.doi.org/10.3390/instruments3010013.

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This paper describes a design approach to a control system of power supply for high-voltage electrochemical processes such as plasma electrolytic oxidation (PEO) or high-voltage anodising (HVA), which require alternating polarisation pulses up to 750 V and a typical current density of 50–500 mA/cm2. Complex characteristics of the electrochemical system response on applied polarisations (positive or negative) cause necessity of precise control of polarising pulse shapes for better process operation and its understanding. A device performs cycle-by-cycle pulse-width modulation (PWM) control, including feedback based on digital analysis of the instantaneous current and/or voltage output, and the desired pulse waveform stored in memory for each output polarity. The output stage has four states corresponding to positive or negative pulses, as well as open- or short-circuit conditions, with respect to an electrochemical cell. A fully programmable controller allows one to generate arbitrary waveforms, as well as their sequences, by means of “regime designer” software. Moreover, a smart feedback system can provide adaptation of the next pulse parameter from analysis of the process prehistory. For instance, this approach allows one to separate main electrochemical process (coating formation) and diagnosis of the phenomenon through introduction of high-voltage triangular voltage sweep pulse within a pause of the main process, which is normally carried out under a current control.

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Pisarenko, Ivan, and Eugeny Ryndin. "Research and development of high-speed on-chip photodetectors based on AIIIBV heterostructures." ITM Web of Conferences 30 (2019): 08003. http://dx.doi.org/10.1051/itmconf/20193008003.

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This paper is aimed at the solution of the fundamental scientific and technical problem of research and development of high-performance optoelectronic devices designed for on- and inter-chip optical interconnecting in integrated circuits. Previously, we developed a laser with a double AIIIBV nanoheterostructure and a functionally integrated optical modulator. The device is based on the principle of controlled spatial relocation of charge carrier density peaks within quantum regions and provides the generation of optical signals with high modulation frequencies. The detection of short laser pulses generated by the lasermodulator requires a technologically compatible on-chip photodetector with subpicosecond response time. To meet the given requirements, we propose a novel design of a high-speed photodetector that employs the same relocation principle as the laser-modulator. The photodetector contains a traditional p-i-n photosensitive structure and an orthogonally oriented control heterostructure. During the back edge of a laser pulse, the control heterostructure displaces the peaks of electron and hole densities into special low-temperature-grown regions with short lifetimes and low carrier mobilities. We developed the quantum mechanical numerical model of the photodetector with controlled relocation of carrier density peaks and estimated the duration of the photocurrent back edge.

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Liu, Xiao Jian, Wei Xu, and Jue Wang. "LDPC Coded PPM and Iterative Detection for Free-Space Optical Links." Applied Mechanics and Materials 651-653 (September 2014): 444–50. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.444.

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The pulse position modulation, which has the advantage of average energy efficiency and bandwidth efficiency, is an attractive modulation scheme for free-space optical communication. An important practical issue is to employ an efficient channel coding to this modulation. In this view, we consider the use of low density parity-check code together with iterative soft demodulation and channel decoding at the receiver. In particular, we discuss the calculation of the soft information at the demodulator to accommodate the LDPC decoder. We show that the proposed scheme is quite efficient against demodulation errors due to the receiver noise.

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Han, Yang, Djordjevic, Yue, Wang, Qu, and Anderson. "Joint Probabilistic-Nyquist Pulse Shaping for an LDPC-Coded 8-PAM Signal in DWDM Data Center Communications." Applied Sciences 9, no. 23 (November 20, 2019): 4996. http://dx.doi.org/10.3390/app9234996.

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M-ary pulse-amplitude modulation (PAM) meets the requirements of data center communication because of its simplicity, but coarse entropy granularity cannot meet the dynamic bandwidth demands, and there is a large capacity gap between uniform formats and the Shannon limit. The dense wavelength division multiplexing (DWDM) system is widely used to increase the channel capacity, but low spectral efficiency of the intensity modulation/direct detection (IM/DD) solution restricts the throughput of the modern DWDM data center networks. Probabilistic shaping distribution is a good candidate to offer us a fine entropy granularity and efficiently reduce the gap to the Shannon limit, and Nyquist pulse shaping is widely used to increase the spectral efficiency. We aim toward the joint usage of probabilistic shaping and Nyquist pulse shaping with low-density parity-check (LDPC) coding to improve the bit error rate (BER) performance of 8-PAM signal transmission. We optimized the code rate of the LDPC code and compared different Nyquist pulse shaping parameters using simulations and experiments. We achieved a 0.43 dB gain using Nyquist pulse shaping, and a 1.1 dB gain using probabilistic shaping, while the joint use of probabilistic shaping and Nyquist pulse shaping achieved a 1.27 dB gain, which offers an excellent improvement without upgrading the transceivers.

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Park, HwaPyeong, Mina Kim, HakSun Kim, and JeeHoon Jung. "Design Methodology of Tightly Regulated Dual-Output LLC Resonant Converter Using PFM-APWM Hybrid Control Method." Energies 12, no. 11 (June 4, 2019): 2146. http://dx.doi.org/10.3390/en12112146.

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A dual-output LLC resonant converter using pulse frequency modulation (PFM) and asymmetrical pulse width modulation (APWM) can achieve tight output voltage regulation, high power density, and high cost-effectiveness. However, an improper resonant tank design cannot achieve tight cross regulation of the dual-output channels at the worst-case load conditions. In addition, proper magnetizing inductance is required to achieve zero voltage switching (ZVS) of the power MOSFETs in the LLC resonant converter. In this paper, voltage gain of modulation methods and steady state operations are analyzed to implement the hybrid control method. In addition, the operation of the hybrid control algorithm is analyzed to achieve tight cross regulation performance. From this analysis, the design methodology of the resonant tank and the magnetizing inductance are proposed to compensate the output error of both outputs and to achieve ZVS over the entire load range. The cross regulation performance is verified with simulation and experimental results using a 190 W prototype converter.

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Wen, Jin, Chengju Ma, Wei Fan, Haiwei Fu, and Zhenan Jia. "Numerical investigation on the femtosecond pulse propagation and free carriers’ evolution in silicon-on-insulator waveguides." Modern Physics Letters B 30, no. 21 (August 10, 2016): 1650299. http://dx.doi.org/10.1142/s0217984916502997.

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The femtosecond pulse propagation and free carriers’ evolution in the silicon-on-insulator (SOI) waveguides have been numerically investigated considering the carrier’s lifetime and the pulse width of the input pulse at 1.5 [Formula: see text]m regime. Numerical results show that the free carriers’ density profile becomes gentle between the leading edge and trailing edge of the pulse in time domain due to the decreasing of the pulse intensity caused by the nonlinear absorption, which becomes more remarkable when the pulse width expands. It can be found that lifetime ranging from 5 ns to 100 ns does not affect the free carriers’ evolution clearly in femtosecond regime. In addition, the refractive index modulation can be appeared in the process of pulse propagation and free carriers evolution with lower peak power of 200 W. This research can supply some contribution to the insight of free carriers evolution in SOI waveguides.

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Ziatdinov, Sergey, and Leonid Osipov. "Suppression of correlated interference by adaptive notch filters under pulse repetition period modulation." Information and Control Systems, no. 3 (June 29, 2021): 53–60. http://dx.doi.org/10.31799/1684-8853-2021-3-53-60.

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Introduction: We discuss the problem of correlated noise suppression by adaptive complex notch filters of various orders. In order to eliminate the dependence of the transmission coefficient of the useful signal on its frequency, the pulse repetition period is modulated. Purpose: Studying the influence of pulse repetition period modulation on the correlated noise suppression coefficient. Methods: The notch filter parameters were optimized with the criterion of minimum average dispersion of correlated noise at the output of the filters during the repetition period modulation. Results: Expressions are obtained for the variance of correlated noise at the output of complex adaptive filters of various orders when the repetition period is modulated. Relationships are given for finding the optimal values of the tuning frequency and coefficients of the notch filters which minimize the correlated noise level at their output. Expressions are obtained for the coefficients of correlated noise suppression by notch filters in the context of pulse repetition period modulation. The graphs are presented showing how the correlated noise suppression coefficient depends on the relative value of the probing signal repetition period deviation for various values of the correlated noise spectral density width at optimal or non-optimal values of the tuning frequency and coefficients of the notch filters. It is shown that the use of probing pulse repetition period modulation leads to a decrease in the correlated noise suppression coefficient. On the other hand, the adaptation of the weighting coefficients for the adopted models of notch filters and correlated interference provides an increase in the suppression coefficient. Practical relevance: When developing or studying correlated noise suppression systems, the obtained results make it possible, taking into account the permissible losses of the suppression coefficient, to reasonably choose the input pulse repetition period deviation value in order to eliminate the effect of “blind” frequencies.

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Kang, Shin-Chul, and Sang-Pil Mun. "High-Frequency Zero Current Soft Switching Inverter with Pulse Density Modulation for Induction Heated Roller." Journal of the Korean Institute of Illuminating and Electrical Installation Engineers 22, no. 7 (July 31, 2008): 49–57. http://dx.doi.org/10.5207/jieie.2008.22.7.049.

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Hutsaliuk, V. Ya, O. M. Yurchenko, and I. S. Zubkov. "PHASE-LOCKED LOOP SYSTEM OF RESONANCE INVERTERS FOR INDUCTION HEATING INSTALATION WITH PULSE DENSITY MODULATION." Tekhnichna Elektrodynamika 2020, no. 5 (August 25, 2020): 35–39. http://dx.doi.org/10.15407/techned2020.05.035.

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Nakatsuka, Takeo, Hideaki Fujita, and Hirofumi Akagi. "Pulse-Density Modulation of a High-Frequency Voltage-Source Inverter for Atmospheric-Pressure Plasma Generation." IEEJ Transactions on Industry Applications 125, no. 5 (2005): 413–19. http://dx.doi.org/10.1541/ieejias.125.413.

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Journal articles on the topic 'Pulse Density Modulation'

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