LC-Resonant and High-Temperature Resistant Acceleration Sensor Based on DSP

2011 ◽  
Vol 105-107 ◽  
pp. 1966-1969
Author(s):  
Tao Guo ◽  
Jie Zhu ◽  
Gui Tang ◽  
Yan Xu
Keyword(s):  
High Temperature ◽  
High Speed ◽  
Space Shuttle ◽  
Digital Signal ◽  
Acceleration Sensor ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Analog To Digital ◽  
Acceleration Sensors ◽  
Low Pass

It is a challenging problem to test the acceleration of the high-speed missiles and space shuttle under high temperature. This paper proposed a design of LC-resonant and high-temperature resistant acceleration sensors about the phenomenon. With the operational amplifier OP4177, it produces the input signal that contents with A/D (Analog to Digital) signal. An eight level low-pass filter MAX291 is used for testing after the signal is regulated. This design mainly uses AD7934 to complete the conversion from analog signals to digital signals. It also recognizes the resonant point of LC acceleration sensor by the DSP （Digital Signal Processing）recognizing program. The acceleration is computed finally by the DSP chip.

Based on the CO2 Gas Shielded Welding Molten Pool Image Edge Detection Algorithm

2013 ◽  
Vol 437 ◽  
pp. 840-844 ◽  
Author(s):  
Xiao Gang Liu ◽  
Bing Zhao
Keyword(s):  
Edge Detection ◽  
Molten Pool ◽  
High Speed ◽  
Vision System ◽  
Detection Algorithm ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Low Pass ◽  
Defect Recognition ◽  
Pool Image

This paper use the passive vision system through high-speed camera collects molten pool images; and then according to the frequency domain characteristics of the weld pool image Butterworth low-pass filter; gradient method for image enhancement obtained after pretreatment. Research Roberts, Sobel, Prewitt, Log, Zerocross, and Canny 6 both traditional differential operator edge detection processing results. Through comparison and analysis of choosing threshold for [0.1, 0. Canny operator can get the ideal molten pool edge character, for subsequent welding molten pool defect recognition provides favorable conditions.

Plasma models and rescaling methods

1984 ◽  
Vol 31 (1) ◽  
pp. 141-151 ◽  
Author(s):  
Philippe Lotte ◽  
M. R. Feix
Keyword(s):  
High Temperature ◽  
Electrostatic Interactions ◽  
Practical Reasons ◽  
Electrostatic Model ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Numerical Studies ◽  
Low Pass ◽  
Vlasov Limit ◽  
High Pass

The plasma models used in analytical or numerical studies exhibit, mainly for practical reasons, symmetry reducing the dimensions of the space. It is not obligatory that the restrictions on the dynamics and the chosen form of the electrostatic interactions should correspond to the same symmetry and this introduces the concept of a d (dynamic), d' (electrostatic) model with d' ≥ d. We show that the crucial parameter is d' – d. For d' – d = 0, the model exhibits both at low and at high temperature the same characteristic plasma frequency. At high temperature we recover the Vlasov limit and the plasma acts as a high-pass filter. For d' – d = 1, the two frequencies (purely collective at high temperature and ‘crystal’ frequency at very low temperature) are different, while in its high temperature (Vlasov) limit the plasma acts as a low-pass filter. Finally if d' – d ≥ 2 there is no longer a Vlasov limit for all values of temperature and density. These properties are obtained through a systematic use of the homothety transformations and a search for the corresponding invariants.

A New Small-Sized Non-Dispersive Infrared (NDIR) Sensor and its Drive/Readout Circuits

2016 ◽  
Author(s):  
Paul C.-P. Chao ◽  
Li-Chi Hsu ◽  
Trong-Hieu Tran
Keyword(s):  
Pulse Width Modulation ◽  
Cmos Process ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Analog To Digital ◽  
Readout Circuits ◽  
Low Pass ◽  
Driver Circuit ◽  
Module Size ◽  
Gas Chamber

A new miniaturized, non-dispersive, infrared (NDIR) sensor for CO2 intended to be installed in mobile phones and its drive/readout circuits are presented in this study. A typical NDIR sensor consists of three main components; an infrared (IR) light-emitter (light source), a gas chamber, a photo detector (PD) light receiver) and the associated drive/readout circuits. The geometry of the gas chamber is optimized to minimize the total module size to approximately 10 mm × 5 mm × 5 mm, which is much smaller than commercially-available gas sensors. Driver and readout circuits are successfully designed and taped out. The driver circuit intends to generate pulse width modulation (PWM) signal to control proper dimming of LED. The readout circuit, which acquires small signal from photo detector then converts to digital values, includes amplifier, low pass filter and analog-to-digital converter (ADC). The proposed circuit is fabricated by the TSMC 0.35-μm CMOS process, where the area is 4.527 mm2 while power consumption is 60.16 mW for the whole chip. The resolution is less than 12 ppm along with time constant is 0.1 sec.

APPLICATION OF THE PLL CONTROL AT THE REALIZATION OF A 16-THROUGH ADC

2018 ◽  
pp. 6-12 ◽  
Author(s):  
R. V. Magerramov
Keyword(s):  
Electronic Device ◽  
Phase Locked Loop ◽  
Low Noise ◽  
Phase Detector ◽  
Modern World ◽  
Voltage Controlled Oscillator ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Analog To Digital ◽  
Low Pass

This article describes the method of converting an analog signal into a digital code using a phase locked loop (PLL) circuit. The functional structure of the voltage-to-digital conversion circuit is considered. The application of the principle of phase-locked loop for controlling the duty cycle of the output signal of a phase detector when the voltage at the positive input of the operational amplifier included in the low-pass filter is investigated. In the modern world, analog-to-digital converters (ADCs) are available in almost every electronic device. The application of different ADC architectures is determined by their parameters and features by circuit and technological implementation. The phase-locked loop with a digital part (16-bit counter, storage register and data transfer interface) allows to obtain a precision analog-to-digital converter, based on a relatively simple circuit design, which has high accuracy and low noise level. Negative feedback of the PLL loop makes it possible to level the error of the passive elements of the low-pass filter (LPF) and the voltage controlled oscillator (VCO). The result of this work is an analysis of the ADC characteristics in the technological basis of 250 nm.

A SiGe HBT 6th-Order 10 GHz Inductor-Less Anti-Aliasing Low-Pass Filter for High-Speed ATI Digitizers

2021 ◽  
pp. 1-14
Author(s):  
Francesco Centurelli ◽  
Pietro Monsurro ◽  
Giuseppe Scotti ◽  
Pasquale Tommasino ◽  
Alessandro Trifiletti
Keyword(s):  
High Speed ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Sige Hbt ◽  
Low Pass

The Study and Simulation of the Fabric Defects Images Restoration

2011 ◽  
Vol 382 ◽  
pp. 88-91
Author(s):  
Li Hong Zhang ◽  
Ying Bo Liang
Keyword(s):  
High Speed ◽  
Inverse Filtering ◽  
Practical Application ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Blind Image Restoration ◽  
Smoothing Filter ◽  
Satisfactory Outcome ◽  
Low Pass ◽  
Blind Image

By using non-negativity and support constraints recursive inverse filtering ,blind image restoration can be realized. But it’s difficult to resolve the proplem of sensitive to noise,so there has been no practical application. In this paper,according to the characteristic of NAS-RIF algorithm and the question of fuzzy by fabric defects images moving at a high-speed line, methods have been introduced, firstly, Adopt boundary keep smoothing filter as the de-noising pretreatment was carried out for image signal; Secondly, in each iteration of restoration,add the low-pass filter link。Thus,the problem of NAS-RIF algorithm is solved well.The simulation results show that this method has a satisfactory outcome both in visual impression and quantitative analysis.

A Method of Acquiring and Processing GIC Signal in High-Speed Rail Track Circuit

2014 ◽  
Vol 1070-1072 ◽  
pp. 755-758
Author(s):  
Yun Feng Ma ◽  
Wei Zong
Keyword(s):  
High Speed ◽  
Signal Acquisition ◽  
High Speed Rail ◽  
High Speed Railway ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Rail Track ◽  
Sampled Signal ◽  
Low Pass ◽  
Track Circuit

The high-speed railway is a typical ground systems, if subjected to a larger GIC, will lead to serious incidents. For the power supply and wiring pattern of high-speed railway is different from the public grid, then how to monitor the GIC impact on the high-speed rail electrical systems need to be studied. The paper study the process and pattem of GIC in high-speed rail track circuit, and propose a signal acquisition method of GIC in the track circuit. The sampled signal will be go through the low-pass filter designed by the window function to obtain the GIC.

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