Study of the Simultaneous Generation of UWB Doublet and Triplet Signals Based on Nonlinear Effects of SOA

2014 ◽  
Vol 599-601 ◽  
pp. 1729-1733
Author(s):  
Xin Qiao Chen ◽  
Yu Chen Zhang ◽  
Lin Tang
Keyword(s):  
Light Source ◽  
Pulse Width ◽  
Input Pulse ◽  
Nonlinear Effects ◽  
Central Frequency ◽  
Simultaneous Generation ◽  
Source Power ◽  
Doublet Signal ◽  
Relative Bandwidth ◽  
Triplet Signal

A scheme that can be used to generate UWB doublet and triplet signals simultaneously based on SOA-SGS and SOA-XGM is carried up, then the theory is analyzed. Simulated through Optisystem9.0, a UWB doublet signal whose central frequency is 6GHz and relative bandwidth is 143% and a triplet signal whose central frequency is 8GHz and relative bandwidth is 120% are generated. Then, the impacts that input pulse width and light source power impose on the results is analyzed.

Psychophysics Study on LED Flicker Artefacts for Automotive Digital Mirror Replacement Systems

2020 ◽  
Vol 2020 (11) ◽  
pp. 234-1-234-6
Author(s):  
Nicolai Behmann ◽  
Holger Blume
Keyword(s):  
Light Source ◽  
Pulse Width ◽  
Digital Camera ◽  
Relevant Information ◽  
Human Vision ◽  
Light Sources ◽  
Traffic Light ◽  
Pulse Width Modulated ◽  
Novel Approach ◽  
Flicker Light

LED flicker artefacts, caused by unsynchronized irradiation from a pulse-width modulated LED light source captured by a digital camera sensor with discrete exposure times, place new requirements for both visual and machine vision systems. While latter need to capture relevant information from the light source only in a limited number of frames (e.g. a flickering traffic light), human vision is sensitive to illumination modulation in viewing applications, e.g. digital mirror replacement systems. In order to quantify flicker in viewing applications with KPIs related to human vision, we present a novel approach and results of a psychophysics study on the effect of LED flicker artefacts. Diverse real-world driving sequences have been captured with both mirror replacement cameras and a front viewing camera and potential flicker light sources have been masked manually. Synthetic flicker with adjustable parameters is then overlaid on these areas and the flickering sequences are presented to test persons in a driving environment. Feedback from the testers on flicker perception in different viewing areas, sizes and frequencies are collected and evaluated.

EFFECTS OF THE WIGGLER ON THE HEFEI LIGHT SOURCE STORAGE RING

2009 ◽  
Vol 24 (05) ◽  
pp. 1057-1067
Author(s):  
HE ZHANG ◽  
MARTIN BERZ
Keyword(s):  
Magnetic Field ◽  
Light Source ◽  
Storage Ring ◽  
Field Model ◽  
Beta Function ◽  
Nonlinear Effects ◽  
Magnetic Field Model ◽  
Dynamic Aperture ◽  
Linear Effects ◽  
The Magnetic Field

The Hefei light source (HLS) is a second generation synchrotron radiation light source, in which a superconducting wiggler is installed and operating. The effects of the wiggler on the beam dynamics on the HLS storage ring are studied, in order to make sure the wiggler can operate properly when the ring is working in the high brilliance mode. We generate a model of the magnetic field in the midplane of the wiggler. The 3D magnetic field model is also builded up by COSY infinity 9.0. Both the linear and nonlinear effects of the wiggler are discussed. The vertical tune is changed from 2.535 to 2.567 and the vertical beta function is heavily distorted, while a symplectic tracking study shows the dynamic aperture is only slightly affected by the wiggler. And the wiggler should be able to run on the high brilliance mode after the linear effects get compensated.

scholarly journals Design of Smart Light Source based on Bi-color LED with Single Duty Cycle for Correlated Color Temperature Adjustment

2021 ◽  
Author(s):  
Lingyuan Qiao ◽  
Huanyue Zhang ◽  
Jingjie Yu ◽  
Fan Cao ◽  
Yingming Gao
Keyword(s):  
Light Source ◽  
Duty Cycle ◽  
Pulse Width ◽  
Pulse Width Modulation ◽  
Color Temperature ◽  
Light Sources ◽  
One To One ◽  
Color Mixing ◽  
The One ◽  
Daylight Harvesting

Abstract Color-adjustable light sources facilitate both mood lighting and daylight harvesting. A single duty cycle can be used by a bi-color LED to adjust the correlated color temperature by associating it with the duty cycle of the pulse width modulation dimming signal of the cold and warm light sources. The one-to-one mapping relationship between the single duty cycle and the correlated color temperature is based on the color mixing theory of bi-color LEDs. A method to correlate the dimming signals for cold and warm LEDs is presented. The influence of the time characteristics of the two basic signals on dimming and color temperature adjustment is analyzed. The dimming system of bi-color LEDs is designed, and the method used to adjust the correlated color temperature with a single duty cycle is verified. The experiment showed that the correlated color temperature can be accurately adjusted by the proposed method.

scholarly journals New Dead-Time Compensation Method of Power Inverter using Carrier Based Sinusoidal Pulse-Width Modulation

2018 ◽  
Vol 8 (6) ◽  
pp. 4880
Author(s):  
Suroso Suroso ◽  
Daru Tri Nugroho ◽  
Toshihiko Noguchi
Keyword(s):  
Pulse Width ◽  
Pulse Width Modulation ◽  
Dead Time ◽  
Compensation Method ◽  
Voltage Source ◽  
Output Current ◽  
Dead Time Correction ◽  
Source Power ◽  
Dead Time Compensation ◽  
Sinusoidal Pulse Width Modulation

<p>A new dead-time compensation method of power inverter circuits is suggested and presented in this paper. The proposed method utilizes carrier based sinusoidal pulse width modulation technique to produce driving signals of the inverter power switches with dead-time correction capability. The proposed method able to eliminate dead-time effects such as reducing the waveform distortion of the inverter output current, and increasing the fundamental component amplitude of output current. An analysis of the proposed method is presented. Some computer simulations were carried out to investigate the principle operation, and to test performance of the new method. The developed method was validated through experimental test of H-bridge voltage source inverter circuits. The data obtained from the computer simulation and prototype experiments have confirmed that that the proposed method worked well compensating the dead-time in the voltage source power inverter circuits.</p>

scholarly journals NONLINEAR EFFECTS IN THE PULSE-WIDTH CONTROL SYSTEM FOR THERMOTECHNICAL OBJECT

2017 ◽  
Vol 2 (9) ◽  
pp. 188-192
Author(s):  
Гольцов ◽  
Yuriy Gol'cov ◽  
Кижук ◽  
Aleksandr Kizhuk ◽  
Рубанов ◽  
...  
Keyword(s):  
Control System ◽  
Pulse Width ◽  
Nonlinear Effects

Numerical investigation on the femtosecond pulse propagation and free carriers’ evolution in silicon-on-insulator waveguides

2016 ◽  
Vol 30 (21) ◽  
pp. 1650299
Author(s):  
Jin Wen ◽  
Chengju Ma ◽  
Wei Fan ◽  
Haiwei Fu ◽  
Zhenan Jia
Keyword(s):  
Pulse Width ◽  
Peak Power ◽  
Femtosecond Pulse ◽  
Pulse Propagation ◽  
Input Pulse ◽  
Leading Edge ◽  
Silicon On Insulator ◽  
Refractive Index Modulation ◽  
Free Carriers ◽  
Femtosecond Regime

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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