DAC Testing Using Impulse Signals

2012 ◽  
Vol 19 (1) ◽  
pp. 105-114 ◽  
Author(s):  
Josef Vedral ◽  
Pavel Fexa
Keyword(s):  
Frequency Domain ◽  
Sine Wave ◽  
Testing Time ◽  
Dynamic Parameters ◽  
Effective Number ◽  
Signal To Noise ◽  
Crest Factor ◽  
Multiple Tests ◽  
Digital To Analog Converters ◽  
Band Signal

DAC Testing Using Impulse SignalsThe Multi-Tone (MT) signal with uniform amplitudes can be used for DAC testing. This paper shows an easier way to generate a MT signal using several impulse signals. The article also analyzes qualities of methods for testing the dynamic parameters of Digital to Analog Converters using an impulse signal. The MT, Damped Sine Wave (DSW) and Sinx/x (SINC) signals will be used as the source for these tests. The Effective Number of Bits (ENOB) and Signal to noise and distortion (SINAD) are evaluated in the frequency domain and they are modified using theCrest Factor(CF) correction and compared with the standard results of the Sine Wave FFT test. The first advantage of the test using an impulse signal is that you need fewer input parameters to create the band signal for testing the DAC. The second one is to reduce the testing time using a band signal in comparison with multiple tests using a single sine wave.

DAC Testing Using Modulated Signals

2011 ◽  
Vol 18 (2) ◽  
pp. 283-294 ◽  
Author(s):  
Pavel Fexa ◽  
Josef Vedral ◽  
Jakub Svatoš
Keyword(s):  
Sine Wave ◽  
Test Methods ◽  
Testing Time ◽  
Effective Number ◽  
Signal To Noise ◽  
Frequency Signal ◽  
Digital To Analog Converters ◽  
Fm Signals ◽  
Dynamical Parameters ◽  
Modulated Signals

DAC Testing Using Modulated Signals This document analyses qualities of methods used for testing dynamical parameters of Digital-to-Analog Converters (DAC) using a multi-frequency signal. As the source for these signals, Amplitude Modulated (AM) and Frequency Modulated (FM) signals are used. These signals are often used in radio engineering. Results of the tests, like Effective Number of Bits (ENOB), Signal-to-Noise and Distortion (SINAD), are evaluated in the frequency domain and they are compared with standard results of Sine Wave FFT test methods. The aim of this research is firstly to test whether it is possible to test a DAC using modulated signals, secondly to reduce testing time, while estimating band performance of DAC.

scholarly journals Dynamic Response of an Inhomogeneous Viscoelastic Pile in a Multilayered Soil to Transient Axial Loading

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Zhiqing Zhang ◽  
Jian Zhou ◽  
Kuihua Wang ◽  
Qiang Li ◽  
Kaifu Liu
Keyword(s):  
Frequency Domain ◽  
Longitudinal Wave ◽  
Soil Layer ◽  
Axial Loading ◽  
Analytical Form ◽  
Sine Wave ◽  
Function Technique ◽  
Cross Sectional ◽  
Soil System ◽  
Single Defect

A quasi-analytical solution is developed in this paper to investigate the mechanism of one-dimensional longitudinal wave propagating in inhomogeneous viscoelastic pile embedded in layered soil and subjected to a transient axial loading. At first, the pile-soil system is subdivided into several layers along the depth direction in consideration of the variation of cross-sectional acoustic impedance of the pile or differences in soil properties. Then, the dynamic governing equation of arbitrary soil layer is established in cylindrical coordinates and arbitrary viscoelastic pile segment is modeled using a single Voigt model. By using the Laplace transform and boundary conditions of the pile-soil system, the vertical impedance at the top of arbitrary pile segment is defined in a closed form in the frequency domain. Then by utilizing the method of recursion typically used in the Transfer Function technique, the vertical impedance at the pile top can be derived in the frequency domain and the velocity response of an inhomogeneous viscoelastic pile subjected to a semi-sine wave exciting force is obtained in a semi-analytical form in the time domain. Selected numerical results are obtained to study the mechanism of longitudinal wave propagating in a pile with a single defect or double defects.

A High Bandwidth Sigma-Delta Modulator Applied in Micro-Gyroscope

2013 ◽  
Vol 562-565 ◽  
pp. 369-373 ◽  
Author(s):  
Qiang Fu ◽  
Wei Ping Chen ◽  
Song Chen ◽  
Peng Fei Wang ◽  
Xiao Wei Liu
Keyword(s):  
Signal To Noise Ratio ◽  
System Simulation ◽  
Sampling Frequency ◽  
Effective Number ◽  
Signal To Noise ◽  
Sigma Delta Modulator ◽  
Sigma Delta ◽  
High Bandwidth ◽  
Oversampling Ratio ◽  
Input Level

In this paper a fourth-order single-loop sigma-delta modulator applied in micro-gyroscope is designed. The modulator system chose the fully feedforword structure. The signal bandwidth is 200KHz, oversampling ratio is 64 and sampling frequency is 25.6MHz. By system simulation result in Matlab, the signal to noise ratio (SNR) is 92.3dB and effective number of bits (ENOB) is 15.03bits. The whole circuit of modulator is designed and simulated in Cadence Spectre. It is gotten that the SNR is 78.6dB and changes linearly with input level. When input level is bigger than -4dBFs, the modulator becomes overload.

scholarly journals Influence of the driving frequency and equivalent parameters on displacement amplitude of electrostatic linear comb actuator

2018 ◽  
Vol 40 (4) ◽  
pp. 397-306
Author(s):  
Hoang Trung Kien ◽  
Vu Cong Ham ◽  
Pham Hong Phuc
Keyword(s):  
Sine Wave ◽  
Displacement Amplitude ◽  
Damping Factor ◽  
Driving Voltage ◽  
Driving Frequency ◽  
Dynamic Parameters ◽  
Motion Direction ◽  
Amplitude Error ◽  
Differential Motion ◽  
Air Damping

A new method determining the equivalent dynamic parameters such as stiffness, vibrating mass, and air damping factor in motion direction of shuttle (i.e. in y-direction) is proposed, thence the differential motion equation of shuttle is established and solved to achieve a typical displacement formula. Simulation and experimental results show that the change of ELCA' displacement is inappreciable while the range of driving frequency up to 27 Hz (error of 10% with driving voltage is a square wave). Moreover, the range of driving frequency for the ELCA can be extended up to 1 kHz with displacement amplitude error of 10% while the shape of driving voltage is a harmonic sine wave.

scholarly journals PERFORMANCE EVALUATION OF SINGLE CARRIER FREQUENCY DOMAIN EQUILIZER (SC-FDE) OVER IMPULSIVE NOISE CHANNEL

2019 ◽  
Vol 11 (2) ◽  
pp. 270-277
Author(s):  
Hussein Abdullah Leftah ◽  
Husham Lateef Swadi
Keyword(s):  
Frequency Domain ◽  
Carrier Frequency ◽  
Communication Systems ◽  
Impulsive Noise ◽  
Signal To Noise Ratio ◽  
High Signal ◽  
Signal To Noise ◽  
Single Carrier ◽  
Noise Ratio ◽  
Error Floors

Impulsive noise is considered as one of the major source of disturbance in the state-of-the-art multicarrier (MC) communication systems. Therefore, several techniques are being constantly proposed to eliminate the effect of such noise. In this work, a time domain matrix interleaved is compiled with a single carrier frequency domain equalizer (SC-FDE) is proposed to reduce the deleterious effects of impulsive noise. A mathematical model for the proposed scheme is also presented in this paper. Simulation results show that the proposed technique superiors the interleaved multicarrier system where the proposed scheme can completely avoid the error floors not only at high signal-to-noise ratio (SNR) but also at heavily distributed impulsive noise. The bit-error-rate (BER) of the alternative proposed scheme decreases as the signal-to-noise ratio (SNR) increases whereas the BER of the standard system suffers from error-floors with a constant BER at about 10-3 for about 8 dB SNR for medium and heavily impulsive noise.

Frequency domain of weakly translation invariant frame MRAs

2021 ◽  
Author(s):  
Zhihua Zhang
Keyword(s):  
Signal Processing ◽  
Data Analysis ◽  
Frequency Domain ◽  
Scaling Function ◽  
Narrow Band ◽  
Scaling Functions ◽  
Translation Invariant ◽  
Frequency Domains ◽  
Band Signal

Frequency domain of bandlimited frame multiresolution analyses (MRAs) plays a key role when derived framelets are applied into narrow-band signal processing and data analysis. In this study, we give a characterization of frequency domain of weakly translation invariant frame scaling functions [Formula: see text] with frequency domain [Formula: see text]. Based on it, we further study convex and ball-shaped frequency domains. If frequency domain of bandlimited frame scaling function [Formula: see text] is convex and completely symmetric about the origin, then it must be weakly invariant and [Formula: see text]. If [Formula: see text] has a ball-shaped frequency domain, the ball radius must be bounded by [Formula: see text]. These frequency domain characters are owned uniquely by frame scaling functions and not by orthogonal scaling functions.

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