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Phase shift effects of radio-frequency bias on ion energy distribution in continuous wave and pulse modulated inductively coupled plasmas
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作者 Chan Xue Fei Gao +2 位作者 Yong-Xin Liu Jia Liu You-Nian Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第4期346-351,共6页
A retarding field energy analyzer(RFEA) is used to measure the time-averaged ion energy distributions(IEDs) on the substrate in both continuous wave(CW) and synchronous pulse modulated radio-frequency(RF) indu... A retarding field energy analyzer(RFEA) is used to measure the time-averaged ion energy distributions(IEDs) on the substrate in both continuous wave(CW) and synchronous pulse modulated radio-frequency(RF) inductively coupled Ar plasmas(ICPs).The effects of the phase shift θ between the RF bias voltage and the RF source on the IED is investigated under various discharge conditions.It is found that as θ increases from 0 to π,the IED moves towards the low-energy side,and its energy width becomes narrower.In order to figure out the physical mechanism,the voltage waveforms on the substrate are also measured.The results show that as θ increases from 0 to π,the amplitude of the voltage waveform decreases and,meanwhile,the average sheath potential decreases as well.Specifically,the potential drop in the sheath on the substrate exhibits a maximum value at the same phase(i.e.,θ = 0) and a minimum value at the opposite phase(i.e.,θ = π).Therefore,when ions traverse across the sheath region above the substrate,they obtain less energies at lower sheath potential drop,leading to lower ion energy.Besides,as θ increases from π to 2π,the IEDs and their energy widths change reversely. 展开更多
关键词 ion energy distribution phase shift synchronous pulse modulated inductively coupled plasmas
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Pulse modulated microwave and infrared thermography for superficial hyperthermia
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作者 马国军 江国泰 陈志宏 《Journal of Central South University》 SCIE EI CAS 2012年第7期1927-1931,共5页
A 3D temperature field distribution of biological tissue for superficial hyperthermia using a pulse modulated microwave (PMMW) was presented. A 3D sliced homogeneous phantom was radiated by the PMMW and an infrared ... A 3D temperature field distribution of biological tissue for superficial hyperthermia using a pulse modulated microwave (PMMW) was presented. A 3D sliced homogeneous phantom was radiated by the PMMW and an infrared thermal imager was applied to image temperature distribution throughout the phantom. The period of the PMMW is 3 s and the output power is 35 W. The temperature rises by at least 3 ℃ in the phantom when the duty cycle varies from 1/3, 1/2, 2/3 to 1 (denoted by scenarios 1-4). Both the accumulative temperature-volume histogram and the relative depth-area ratio histogram show that the maximum temperature rise (MTR) is 6.6 and 8 ℃ in scenarios 2 and 3, and they are superior to scenarios 1 and 4. Furthermore, the PMMW can control temperature field distribution of biological tissue. It provides both preliminary basis for thermal volume control and new technology for temperature control and monitor in superficial hyperthermia. 展开更多
关键词 3D temperature field distribution pulse modulated microwave (PMMW) infrared thermography superficialhyperthermia
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Behavior of Benzene Decomposition by Using Pulse Modulated Power Supply 被引量:2
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作者 姜华东 马天鹏 钟方川 《Journal of Donghua University(English Edition)》 EI CAS 2015年第3期493-497,共5页
For improving the energy efficiency of plasma volatile organic compounds( VOCs) decomposition, a pulse modulated power is used to drive the dielectric barrier discharge( DBD) plasma to treat benzene. Through the chang... For improving the energy efficiency of plasma volatile organic compounds( VOCs) decomposition, a pulse modulated power is used to drive the dielectric barrier discharge( DBD) plasma to treat benzene. Through the change of pulse duty cycle,the pulse modulation effect on benzene removal energy efficiency was investigated. The results show that pulse modulation can improve the energy yield and reduce the temperature of the chamber wall. There is an optimal duty cycle for achieving the maximum energy yield at a certain discharge voltage. The effect of initial benzene concentration on the decomposition efficiency and carbon selectivity in pulse modulation plasma were studied. The results indicate that the removal efficiency and carbon balance increase with the specific input energy( SIE) and decrease with the concentration. The energy yield increases with increasing initial concentration and achieves maximum around 180 J / L SIE for all initial concentrations. 展开更多
关键词 pulse modulation benzene decomposition dielectric barrier discharge(DBD) energy yield
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One-Dimensional Fluid Model of Pulse Modulated Radio-Frequency SiH_4 /N_2 /O_2 Discharge
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作者 王燕 刘相梅 +1 位作者 宋远红 王友年 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第2期107-110,共4页
Driven by pulse modulated radio-frequency plasma in capacitively coupled discharge are studied by source, the behavior of SiH4/N2/02 using a one-dimensional fluid model. Totally, 48 different species (electrons, ions... Driven by pulse modulated radio-frequency plasma in capacitively coupled discharge are studied by source, the behavior of SiH4/N2/02 using a one-dimensional fluid model. Totally, 48 different species (electrons, ions, neutrals, radicals and excited species) are involved in this simulation. Time evolution of the particle densities and electron temperature with different duty cycles are obtained, as well as the electronegativity nsiH-3 /ne of the main negative ion (Sill3 ). The results show that, by reducing the duty cycle, higher electron temperature and particle density can be achieved for the same average dissipated power, and the ion energy can also be effectively reduced, which will offer evident improvement in plasma deposition processes compared with the case of continuous wave discharge. 展开更多
关键词 pulsed modulation SiH4/N2/02 discharge capacitively coupled plasma fluidmodel
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Hybrid Simulation of Duty Cycle Influences on Pulse Modulated RF SiH_4/Ar Discharge
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作者 王喜凤 宋远红 +2 位作者 赵书霞 戴忠玲 王友年 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第4期394-399,共6页
A one-dimensional fluid/Monte-Carlo(MC)hybrid model is developed to describe capacitively coupled SiH_4/Ar discharge,in which the lower electrode is applied by a RF source and pulse modulated by a square-wave,to inv... A one-dimensional fluid/Monte-Carlo(MC)hybrid model is developed to describe capacitively coupled SiH_4/Ar discharge,in which the lower electrode is applied by a RF source and pulse modulated by a square-wave,to investigate the modulation effects of the pulse duty cycle on the discharge mechanism.An electron Monte Carlo simulation is used to calculate the electron energy distribution as a function of position and time phase.Rate coefficients in chemical reactions can then be obtained and transferred to the fluid model for the calculation of electron temperature and densities of different species,such as electrons,ions,and radicals.The simulation results show that,the electron energy distribution f(ε)is modulated evidently within a pulse cycle,with its tail extending to higher energies during the power-on period,while shrinking back promptly in the afterglow period.Thus,the rate coefficients could be controlled during the discharge,resulting in modulation of the species composition on the substrate compared with continuous excitation.Meanwhile,more negative ions,like Si H_3^-and Si H_2^-,may escape to the electrodes owing to the collapse of ambipolar electric fields,which is beneficial to films deposition.Pulse modulation is thus expected to provide additional methods to customize the plasma densities and components. 展开更多
关键词 hybrid model EEDF pulse modulation SiH_4/Ar mixture
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Pulsed Modulation in Electro-Hyperthermia
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作者 Janos Szucs Lajos Konyha +1 位作者 Gabor Kertesz Andras Szasz 《Open Journal of Biophysics》 2024年第4期374-398,共25页
Modulated electro-hyperthermia (mEHT) is one of the novel oncological treatments with many preclinical and clinical results showing its advantages. The basis of the method is the synergy of thermal and nonthermal effe... Modulated electro-hyperthermia (mEHT) is one of the novel oncological treatments with many preclinical and clinical results showing its advantages. The basis of the method is the synergy of thermal and nonthermal effects, similar to the thermal action of conventional hyperthermia combined with ionizing radiation (radiotherapy). The electric field and the radiofrequency current produced both the thermal and nonthermal processes. The thermal effects produce the elevated temperature as a thermal background to optimize the nonthermal impacts. The low frequency amplitude modulation ensures accurate targeting and promotes immunogenic cell death to develop the tumor specific memory T cells disrupting the malignant cells by immune surveillance. This process (abscopal effect) works like a vaccination. The low frequency amplitude modulation is combined in the new method with the high power pulses for short time, increasing the tumor distortion ability of the electric field. The new modulation combination has much deeper penetration triplicating the active thickness of the effective treatment. The short pulse absorption increases the safety and decreases the thermal toxicity of the treatment, making the treatment safer. The increased power allows for reduced treatment time with the prescribed dose. 展开更多
关键词 Tumor pulsed Modulation Nonthermal Excitation Thermal Homeostasis Cell-Killing RF Current Immunogenic Cell Death Apoptosis
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Research on sinusoid modulated pulse MIG welding methodology 被引量:5
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作者 魏仲华 陈小峰 薛家祥 《China Welding》 EI CAS 2011年第4期75-80,共6页
This article proposed a new methodology and the principle of sinusoid modulated pulse MIG welding, and systematically established the universal mathematical model of computation of the parameters of the sinusoid modul... This article proposed a new methodology and the principle of sinusoid modulated pulse MIG welding, and systematically established the universal mathematical model of computation of the parameters of the sinusoid modulation pulse, achieving that the welding energy input can be effectively controlled and precisely regulated, the transition of pulse change is smooth and the welding process is stable and reliable. With the characteristics of sinusoidal waveform, such as infinite derivative continuity, eternal periodicity and limited control parameters, this article established the theoretical foundation for choiceness, unification and optimization of the parameters during the new sinusoid modulated pulse MIG welding. Bead-on-plate overlay welding is carried out on the pure aluminum sheet test sample for the test. The result indicated that during the welding process, the real-time current waveform is stable and clear; both the corresponding voltage and the instant welding energy waveform are very stable; the repeatability of the U-I graph plotted is high; its family of lines is clear, neat, and its distribution is concentrated showing that the welding process is stable and the neat and high quality ripple weld seam may be produced. 展开更多
关键词 sinusoid modulation sinusoid modulated pulse MIG welding parameter tuning
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Indirect Vector Control of Linear Induction Motors Using Space Vector Pulse Width Modulation 被引量:1
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作者 Arjmand Khaliq Syed Abdul Rahman Kashif +5 位作者 Fahad Ahmad Muhammad Anwar Qaisar Shaheen Rizwan Akhtar Muhammad Arif Shah Abdelzahir Abdelmaboud 《Computers, Materials & Continua》 SCIE EI 2023年第3期6263-6287,共25页
Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.T... Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.This research aims to present a novel framework for speed and thrust force control of LIM using space vector pulse width modulation(SVPWM)inverters.The framework under consideration is developed in four stages.To begin,MATLAB Simulink was used to develop a detailed mathematical and electromechanical dynamicmodel.The research presents a modified SVPWM inverter control scheme.By tuning the proportional-integral(PI)controller with a transfer function,optimized values for the PI controller are derived.All the subsystems mentioned above are integrated to create a robust simulation of the LIM’s precise speed and thrust force control scheme.The reference speed values were chosen to evaluate the performance of the respective system,and the developed system’s response was verified using various data sets.For the low-speed range,a reference value of 10m/s is used,while a reference value of 100 m/s is used for the high-speed range.The speed output response indicates that themotor reached reference speed in amatter of seconds,as the delay time is between 8 and 10 s.The maximum amplitude of thrust achieved is less than 400N,demonstrating the controller’s capability to control a high-speed LIM with minimal thrust ripple.Due to the controlled speed range,the developed system is highly recommended for low-speed and high-speed and heavy-duty traction applications. 展开更多
关键词 Space vector pulse width modulation linear induction motor proportional-integral controller indirect vector control electromechanical dynamic modeling
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Numerical simulation of atmospheric pulsemodulated radio-frequency glow discharge ignition characteristics assisted by a pulsed discharge
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作者 Chengxian PAN Zhengming SHI +2 位作者 Qianhan HAN Ying GUO Jianjun SHI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第1期53-57,共5页
A one-dimensional self-consistent fluid numerical model was developed to study the ignition characteristics of a pulsc-tmxlulated(PM)radio-frequency(RF)glow discharge in atmospheric helium assisted by a sub-microsecon... A one-dimensional self-consistent fluid numerical model was developed to study the ignition characteristics of a pulsc-tmxlulated(PM)radio-frequency(RF)glow discharge in atmospheric helium assisted by a sub-microsecond voltage excited pulsed discharge.The temporal evolution of discharge current density and electron density during PM RF discharge burst was investigated to demonstrate the discharge ignition characteristics with or without the pulsed discharge.Under the assistance of pulsed discharge,the electron density in RF discharge burst reaches the magnitude of 1.87 x 1017-3m within 10 RF cycles,accompanied by the formation of sheath structure.It proposes that the pulsed discharge plays an important role in the ignition of PM RF discharge burst.Furthermore,the dynamics of PM RF glow discharge arc demonstrated by the spatiotcmporal evolution of the election density with and without pulsed discharge.The spatial profiles of electron density,electron energy and electric field at specific time instants arc given to explain the assistive role of the pulsed discharge on PM RF discharge ignition. 展开更多
关键词 atmospheric glow discharge numerical simulation discharge ignition pulse modulation
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Numerical study on peak current in pulse-modulated radio-frequency discharges with atmospheric helium–oxygen admixtures
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作者 Xucheng WANG Shuhan GAO Yuantao ZHANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第8期77-83,共7页
Atmospheric pressure pulse-modulated radio-frequency(rf) plasmas have drawn growing attention due to their potential in applications.By selecting appropriate modulation parameters,the diffused and large-volume plasma ... Atmospheric pressure pulse-modulated radio-frequency(rf) plasmas have drawn growing attention due to their potential in applications.By selecting appropriate modulation parameters,the diffused and large-volume plasma can be generated in the pulse-modulated rf plasma with plenty of reactive oxygen species,which is essential for the biomedical application of helium–oxygen plasmas.In this paper,by means of a fluid model,the formation of the peak current in the first period(PCFP) in a pulse-modulated rf helium–oxygen discharge driven by a sinusoidal voltage is discussed,the existence of a reverse field near the anode caused by the negative and positive charges contributes greatly to the mechanism of PCFP.In the simulation,as oxygen admixture increases,the negative ions of O~- and O~-become dominative anions in the sheath region,which can’t be driven to the anode very quickly to build a reverse field,thus the PCFP eventually disappears.This study can effectively enhance the understanding of different transportation behavior of heavy negative ions and electrons,and further optimize pulsemodulated rf discharges with helium–oxygen mixtures in various applications. 展开更多
关键词 pulse modulation RF discharge fluid model
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Efficient combination and enhancement of high-power mid-infrared pulses in plasmas
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作者 朱兴龙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第2期1-5,共5页
High-power intense optical sources in the mid-to-long wavelength infrared region are very attractive for a wide range of fields from fundamental research to materials science and biology applications.However,there are... High-power intense optical sources in the mid-to-long wavelength infrared region are very attractive for a wide range of fields from fundamental research to materials science and biology applications.However,there are still significant challenges in extending long-wavelength infrared pulses into the relativistic regime using conventional optical techniques.Here,based upon a new type of plasma-based optical method,we present an efficient scheme capable of combining several high-power long-wavelength infrared laser pulses into one single,more intense pulse,thus bringing the intensity of the output pulse to the relativistic regime.Such intense infrared pulses will open up new possibilities for strong-field physics and ultrafast applications.Furthermore,this is beneficial to understand the underlying physics and nonlinear processes of modulation,propagation and energy transfer of high-power intense laser pulses in plasmas. 展开更多
关键词 laser plasma interaction infrared pulses plasma optics pulse modulation energy transfer
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NUMERICAL SIMULATION OF THE TEMPERATURE FIELD IN A SOLDER BALL UNDER PULSED LASER AND ITS EFFECT ON THE VIBRATION OF THE SOLDER 被引量:3
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作者 C. Q. Wang M. Y. Li and L. Fang (National Key Laboratory of Advanced Welding Production Technology, H. I. T., Harbin 150001, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期168-172,共5页
The research presented here is focused on the vibration condition of a small volume solder solder ball,which is placed on the surface of a soldering pad and is exerted a pulse modulated continuous wave laser heat sour... The research presented here is focused on the vibration condition of a small volume solder solder ball,which is placed on the surface of a soldering pad and is exerted a pulse modulated continuous wave laser heat source. Finite element method is applied to analyzed the temperature field in the solder ball, and experi- ment is conducted to test the vibration. the results show that,that, the temperature field flucturates with the same frequency as that of the laser pulse, which in turn causes a forced vibration of the same frequency in the liquid solder ball. 展开更多
关键词 pulse modulated continuous wave laser finite element analysis forced vibration
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An Optoelectronic Pulse Frequency Modulation Circuit for Retinal Prosthesis
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作者 刘金彬 陈弘达 +2 位作者 高鹏 裴为华 隋晓红 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期700-704,共5页
A pulse frequency modulation(PFM) circuit for retinal prosthesis,which generates electrical pulses with frequency proportional to the intensity of incident light, is presented. The fundamental characteristic of the ... A pulse frequency modulation(PFM) circuit for retinal prosthesis,which generates electrical pulses with frequency proportional to the intensity of incident light, is presented. The fundamental characteristic of the circuit is described and analyzed. The circuit is realized in 0.6μm CMOS process,and the simulation results testify to the possibility of sub-retinal implantation. 展开更多
关键词 retinal prosthesis sub-retinal implant pulse frequency modulation
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A NOVEL AERONAUTICAL STATIC INVERTER WITH HIGH FREQUENCY PULSE DC LINK
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作者 陈道炼 刘志政 +1 位作者 严仰光 胡育文 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期48-54,共7页
A new combined soft switching technique and a novel topology of aeronautical static inverter with high frequency pulse dc link are proposed in this paper, namely an electrical isolated converter can realize soft swi... A new combined soft switching technique and a novel topology of aeronautical static inverter with high frequency pulse dc link are proposed in this paper, namely an electrical isolated converter can realize soft switching of two stage cascade converters. It lays technical foundation for high power density, high efficiency and low cost aeronautical static inverter. The operation and design approach of this topology are carefully analyzed and studied. The validity of this topology is verified by simulation and test. 展开更多
关键词 INVERTERS high frequency links active clamp circuits combined soft switching techniques three state discrete pulse modulation
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Research of a fractional-turn ratio saturable pulse transformer and its application in a microsecond-range pulse modulator 被引量:4
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作者 Rong CHEN Jianhua YANG +1 位作者 Xinbing CHENG Zilong PAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第6期95-101,共7页
As a combination device for a step-up pulse transformer and a magnetic switch,the saturable pulse transformer is widely used in pulsed-power and plasma technology.A fractional-turn ratio saturable pulse transformer is... As a combination device for a step-up pulse transformer and a magnetic switch,the saturable pulse transformer is widely used in pulsed-power and plasma technology.A fractional-turn ratio saturable pulse transformer is constructed and analyzed in this paper.Preliminary experimental results show that if the primary energy storage capacitors are charged to 300 V,an output voltage of about 19 kV can be obtained across the capacitor connected to the secondary windings of a fractional-tum ratio saturable pulse transformer.Theoretical and experimental results reveal that this kind of pulse transformer is not only able to integrate a step-up transformer and a magnetic switch into one device,but can also lower the saturable inductance of its secondary windings,thus leading to the relatively high step-up ratio of the pulse transformer.Meanwhile,the application of the fractional-turn ratio saturable pulse transformer in a μs range pulse modulator as a voltage step-up device and main switch is also included in this paper.The demonstrated experiments display that an output voltage with an amplitude of about 29 kV,and a 1.6 μs pulse width can be obtained across a 3500 Ω resistive load,based on a pulse modulator,if the primary energy storage capacitors are charged to 300 V.This compact fractional-turn ratio saturable pulse transformer can be applied in many other fields such as surface treatment,corona plasma generation and dielectric barrier discharge. 展开更多
关键词 fractional-turn ratio saturable transformer magnetic switch pulse modulator
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Simultaneous range and radial velocity estimation with a single narrowband LFM pulse 被引量:6
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作者 Chunmao Yeh Jian Yang +1 位作者 Xiuming Shan Yingning Peng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期372-377,共6页
The mismatch effect induced by the radial motion of a target is analyzed for linear frequency modulated (LFM) signals. Then, a novel integrated processing scheme is proposed to re- solve the delay-Doppler coupling e... The mismatch effect induced by the radial motion of a target is analyzed for linear frequency modulated (LFM) signals. Then, a novel integrated processing scheme is proposed to re- solve the delay-Doppler coupling effect in LFM pulse compression. Therefore the range and radial velocity of the target can be si- multaneously estimated with a narrowband LFM pulse. Finally, numerical simulation results demonstrate the effectiveness and good performance of the proposed method. 展开更多
关键词 delay-Doppler coupling motion estimation linear fre- quency modulated (LFM) pulse extended filtering.
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CONTROL STRATEGY FOR ELECTRO-HYDRAULIC POSITION SERVO SYSTEM WITH GENERALIZED PULSE CODE MODULATION 被引量:1
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作者 LIU Rong PAN Huachen CHEN Ying 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第3期50-53,共4页
A hybrid control strategy has been designed and developed for the electro-hydraulic posi-tion servo control system with generalized Pulse code modulation (GPCM), which is suitable for the area where the work conditi... A hybrid control strategy has been designed and developed for the electro-hydraulic posi-tion servo control system with generalized Pulse code modulation (GPCM), which is suitable for the area where the work condition is poor and a large flow rate is required. It is difficult to control the GPCM system because the system is discrete. With consideration of the stability and speediness of the GPCM position servo control system, a control strategy is developed through the theoretical and ex-perimental analyses. The control strategy integrates the merits of Bang-Bang control, PID control and fuzzy control. With this hybrid control strategy, the electro hydraulic control system has good per-formances, and the servo control is carried out with GPCM through on-off valves. 展开更多
关键词 Generalized pulse code modulation (GPCM) Position control Electro hydraulic control
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Operation Mode on Pulse Modulation in Atmospheric Radio Frequency Glow Discharges 被引量:1
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作者 张杰 郭颖 +2 位作者 黄晓江 张菁 石建军 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第10期974-977,共4页
The discharge operation regime of pulse modulated atmospheric radio frequency (RF) glow discharge in helium is investigated on the duty cycle and frequency of modulation pulses. The characteristics of radio frequenc... The discharge operation regime of pulse modulated atmospheric radio frequency (RF) glow discharge in helium is investigated on the duty cycle and frequency of modulation pulses. The characteristics of radio frequency discharge burst in terms of breakdown voltage, alpha(s)- gamma(γ) mode transition voltage and current are demonstrated by the discharge current voltage characteristics. The minimum breakdown voltage of RF discharge burst was obtained at the duty cycle of 20% and frequency of 400 kHz, respectively. The α-γ mode transition of RF discharge burst occurs at higher voltage and current by reducing the duty cycle and elevating the modulation frequency before the RF discharge burst evolving into the ignition phase, in which the RF discharge burst can operate stably in the γ mode. It proposes that the intensity and stability of RF discharge burst can be improved by manipulating the duty cycle and modulation frequency in pulse modulated atmospheric RF glow discharge. 展开更多
关键词 pulse modulation atmospheric glow discharge discharge operation mode
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Chaotic pulse position modulation ultra-wideband system based on particle filtering 被引量:1
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作者 李辉 Zhang Li 《High Technology Letters》 EI CAS 2013年第1期48-52,共5页
Traditional chaotic pulse position modulation(CPPM)system has many drawbacks.It introduces delay into the feedback loop,which will lead to divergence of chaotic map easily.The wrong decision of data will cause error p... Traditional chaotic pulse position modulation(CPPM)system has many drawbacks.It introduces delay into the feedback loop,which will lead to divergence of chaotic map easily.The wrong decision of data will cause error propagation.Mismatch of parameters and synchronization error between the receiver and transmitter will arouse high bit error rate.To solve these problems,a demodulation algorithm of CPPM based on particle filtering is proposed.According to the mathematical model of the system,it tracks the real signal by online separation in demodulation.Simulation results show that the proposed method can track the true signal better than the traditional CPPM scheme.What's more,it has good synchronization robustness,reduced error propagation by wrong decision and low bit error rate. 展开更多
关键词 chaotic communications chaotic pulse position modulation (CPPM) particle filtering ULTRA-WIDEBAND
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Ultra-low power anti-crosstalk collision avoidance light detection and ranging using chaotic pulse position modulation approach 被引量:2
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作者 郝杰 巩马理 +4 位作者 杜鹏飞 卢宝杰 张帆 张海涛 付星 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期250-257,共8页
A novel concept of collision avoidance single-photon light detection and ranging(LIDAR) for vehicles has been demonstrated, in which chaotic pulse position modulation is applied on the transmitted laser pulses for r... A novel concept of collision avoidance single-photon light detection and ranging(LIDAR) for vehicles has been demonstrated, in which chaotic pulse position modulation is applied on the transmitted laser pulses for robust anti-crosstalk purposes. Besides, single-photon detectors(SPD) and time correlated single photon counting techniques are adapted, to sense the ultra-low power used for the consideration of compact structure and eye safety. Parameters including pulse rate, discrimination threshold, and number of accumulated pulses have been thoroughly analyzed based on the detection requirements, resulting in specified receiver operating characteristics curves. Both simulation and indoor experiments were performed to verify the excellent anti-crosstalk capability of the presented collision avoidance LIDAR despite ultra-low transmitting power. 展开更多
关键词 collision avoidance chaotic pulse position modulation time-correlated single photon counting anti-crosstalk
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