Construction of a High-Pass Digital Filter From a Low-Pass Digital Filter
|
|
- Roland Summers
- 6 years ago
- Views:
Transcription
1 TECHNICAL NOTES JOURNAL OF APPLIED BIOMECHANICS, 1994,10, Q 1994 by Human Kinetics Publishers, Inc. Construction of a High-Pass Digital Filter From a Low-Pass Digital Filter Stephen D. Murphy and D. Gordon E. Robertson To remove low-frequency noise from data such as DC-bias from electromyograms (EMGs) or drift from force transducers, a high-pass filter was constructed from a low-pass filter of known characteristics. A summary of the necessary steps required to transform the low-pass digital were developed. Contaminated EMG and force platform data were used to test the filter. The high-pass filter successfully removed the low-frequency noise from the EMG signals. The high-pass filter was then cascaded with the low-pass filter to produce a band-pass filter to enable simultaneous high- and low-frequency noise reduction. The smoothing of displacement signals prior to time differentiation is essential to remove high-frequency artifacts. Higher frequencies become amplified during the differentiation process (see Winter, 1990). To remove highfrequency noise, low-pass digital filters are frequently used. A similar situation occurs when low-frequency noise is present in a signal that needs to be integrated. Even a relatively small bias error, upon integration, can become the dominant component of the signal. The solution is a high-pass filter, which removes the low-frequency interference and leaves the higher frequencies unaffected. Digital high-pass filters are rarely used in biomechanics. These filters could be valuable when low-frequency noise, such as amplifier drift, occurs during electromyography (EMG), accelerometry, or dynamometry. The goal of this research was to develop a high-pass digital filter using the same software already developed for performing low-pass digital filtering, since most biomechanics researchers already possess such technology. Pezzack, Norman, and Winter (1977) showed that the process of digitally filtering cinefilm coordinate data to remove high-frequency noise and then applying finite differences was an appropriate solution for obtaining segmental kinematics. More detail on the construction of the low-pass filter used by Pezzack et al. can be found in Rader and Gold (1967) and Winter (1990). Barr and Chan (1986) constructed low-pass, high-pass, band-pass, and band-stop digital filters based on a transformation from an analog low-pass filter. Barr and Chan's approach did not take advantage of the current knowledge that exists regarding the construction of low-pass digital filters to build high-pass digital filters. A high-pass digital filter can be constructed from a low-pass digital Stephen D. Murphy and D. Gordon E. Robertson are with the School of Human Kinetics, University of Ottawa, Ottawa, ON Canada KIN 6N5.
2 High-Pass Digital Filter 375 filter by means of a transformation. A brief presentation of this derivation, as well as applications of the high-pass digital filter follows. For a more detailed description of the theory behind this approach, consult the text by Oppenheim and Schafer (1989), who developed the principles upon which this transformation is made, but who did not provide a specific example with validation of its effects. Theory The general Nth order digital filter is a recursive equation of the form (Hamming, 1977) N N Therefore, a second order (N = 2) digital filter is written Yn = aoxn + alxn-l + W n-2 + b,y,-t + b2yn-2. Let the known low-pass digital filter have the following transfer function: To get the corresponding high-pass digital filter let (Oppenheim & Schafer, 1989) where and q, = angular velocity of low-pass filter (radls), wp = angular velocity of highpass filter (radls), and T = sampling interval (seconds). Expanding and regrouping the constants into the same form as (Equation 1) yields the high-pass filter with the following coefficients:
3 376 Murphy and Robertson Before the coefficients for the low-pass filter can be calculated, a suitable low-pass cutoff frequency must be chosen. Since the high-pass cutoff frequency is given and the low-pass cutoff frequency can be chosen arbitrarily based on a, set a = 0 and solve for a&,. Choosing a = 0 simplifies the calculations of the high-pass filter coefficients (see Equation 3) and Equation 2 implies that qqt + Q,~T = a. Solving for wp gives qp = Since researchers usually deal with frequencies rather than angular velocities, recall that mq = 27tfhp- Perform a similar substitution for ol, and simplify to get To summarize, use the following steps to build a high-pass digital filter: 1. After selecting the desired cutoff frequency for the high-pass filter, use Equation 4 to calculate the associated low-pass filter's cutoff frequency,.hq. 2. Next, compute the low-pass filter's coefficients (Ai and Bj) using the usual equations. We recommend a zero-lag, Butterworth, critically damped filter as presented by Winter (1990) (for suitable equations, see below). 3. Then by letting a = 0 in Equation 3, the new coefficients, a, and bi, for the high-pass digital filter will be 4. Finally, filter the data using the same equation as for the low-pass filter but using the coefficients, ai and bj, instead of Ai and Bi. As an example, the following steps were used to construct a high-pass filter from the critically damped, Butterworth, low-pass zero-lag filter as described by Winter (1990). First, assume that the researcher has sampled the data at a frequency, f,. Using Equation 4, the associated low-pass cutoff frequency is Note that the cutoff frequency, j,, must be less than one half the sampling rate, f,; otherwise, an aliasing error will occur due to violation of the sampling theorem. Second, determine the cutoff frequency of the associated low-pass filter (see Winter, 1990): o, = tan [n(f;&)]. Third, correct for the number of filter passes of the critically damped, zero-lag filter (Robertson, Barden, & Dowling, 1992). The corrected cutoff is where n is the number of filter passes. In the case of a zero-lag filter where the data are passed (cascaded) through the filter twice (once in the forward direction and once in the backwards direction) n will be 2. Fourth, compute the low-pass filter coefficients. Let Kl = 203,* and K1 = Then, the low-pass coefficients are as follows:
4 High-Pass Digital Filter Fifth, from Equation 5 above, the high-pass coefficients are a, = A, a, = -Al, a2 = A,, b, = -B,, and b2 = B2. Finally, filter the data by running them through the filter first in the forwards direction and then in the reverse direction. This will produce a zero-lag filter with a roll-off of fourth order (i.e., -24 db/ octave). The equation of the filter is yi = a,gi + alxi-~ + a24-~ + blyi-i + boi-2, where, 4 are the raw data and yi are the filtered data. Methods Four applications of the high-pass digital filter demonstrate its usefulness in removing low-frequency noise. In the first two applications, a high-pass filter was constructed and applied to two 6-second samples of EMG from a series of flexor digitorurn longus muscle contractions. ~ ach signal was collected at approximately 2100 Hz. The first EMG had a DC-bias of 0.13 mv added while the second sample had a drift of 0.42 mv/s added. The third application was a vertical force history that was collected from a piezoelectric force platform (Kistler Model 9865B) with the "time constant" option set (Bioware Version 2.0, Kistler Corp.) to produce drift. This is similar to using the "long" time constant on the older Kistler Model 9261A force platforms. The subject stood on the platform and performed a series of deepknee bends. In the fourth application, a digitally constructed signal containing 0.1, 1.O, and 10.0 Hz sine waves, all with unity amplitude, was constructed. Low-pass and high-pass filters were designed in the same manner as above. The multifrequency signal was both high-pass and low-pass filtered and then was filtered with both the high-pass and low-pass filters providing a band-pass filter. Results and Discussion Figure 1 shows the frequency response of the high-pass filter. Notice that this filter is very flat in the pass band. This is a property of Butterworth filters, which are designed to be optimally flat in the pass band. In Figure 2, a raw EMG signal with a DC-offset is displayed. Below it in the same figure is the signal after applying a high-pass filter with a cutoff frequency of 1.0 Hz. The filter successfully removed the bias from the signal without adversely influencing the amplitudes of the high-frequency components. Note that the closely dotted line in the middle of this and the following figures are the zero voltage levels. Both curves have the same scaling factor, which is displayed to the right beside each curve. The time-axis scaling is displayed in the bottom right-hand side of each figure. Figure 3 shows a similar EMG that had "drift" present. The lower curve was filtered at 1.0 Hz, which completely removed the drift but left the EMG amplitudes unaffected. These results demon-
5 uoswqo~ pue Ayd~n~
6 High-Pass Digital Filter 3 79 Figure 3 - Effects of a high-pass filter on an EMG signal with "drift." strate the usefulness of a high-pass filter for removing unwanted low-frequency noise from EMG signals. In Figure 4 a vertical force history with drift due to using a piezoelectric force platform (Kistler) with a low time constant is shown. After 12 seconds, the apparent body weight of the subject dropped from 717 N to 633 N. After running the data through a high-pass filter with a 0.5 Hz cutoff the body weight line was reduced to zero. This was expected because a high-pass filter acts like ac-coupling and so the dc-offset produced by the subject's body weight was removed from the signal, as shown by the middle curve in Figure 4. The lower curve shows the force signal after the body weight of 717 N was added back. This signal very closely matches the original signal, except that the drift due to the low time constant has been removed. Notice that there is a slight artifact present in the first second of the filtered signal. This is due to the "warm-up" that is needed before the filter functions correctly. These effects can be reduced by having lead-in data to allow the filter time to settle. Figure 5 shows the results of both high-pass and low-pass filtering a signal containing 0.1, 1.0, and 10.0 Hz sine waves. The top curve is the raw data, the second curve shows the data high-pass filtered with a 0.5 Hz cutoff, and the third curve shows the effects of low-pass filtering at 5.0 Hz. The bottom curve demonstrates the effects of cascading the data through a 0.5 Hz high-pass filter followed by a 5.0 Hz low-pass filter. Examining the second and bottom curves shows that the low frequency 0.1 Hz signal is no longer present. Its signal amplitude has been reduced to 3% of its original amplitude. The higher frequency 10 Hz signal has also been reduced (to 12%) in the third and bottom curves, but is still visible in the filtered signals. Lowering the low-pass filter's cutoff would
7 -leu%!s p3!8!p dauanbaq -!Jlnur e jo %u!ja~g ssed-pueq pue bssed-~ol bssed-qs!q jo spa333 - s a~n%!& uosllaqo~ pue Ayd~nw 08E
8 High-Pass Digital Filter 381 reduce the 10 Hz signal more, but the amplitude of the 1.0 Hz signal will also be reduced. Again, notice that these filters do require time to reach their specified operating characteristics. In the case of zero-lag filters, extra leading and trailing data are required (see Smith, 1989). References Barr, R.E., & Chan, E.K.Y. (1986). Design and implementation of digital filters for biomedical signal processing. Journal of Electrophysiological Techniques, 13, Hamming, R.W. (1977). Digitalfilters. Englewood Cliffs, NJ: Prentice Hall. Oppenheim, A.V., & Schafer, R.W. (1989). Discrete-time signal processing. Englewood Cliffs, NJ: Prentice Hall. Pezzack, J.C., Norman, R.W., & Winter, D.A. (1977). An assessment of derivative determining techniques used for motion analysis. Journal of Biomechanics, 10, Rader, C.M., & Gold, B. (1967). Digital filtering design techniques in the frequency domain. Proceedings of leee, 55, Robertson, D.G.E., Barden, J., & Dowling, J. (1992). In Proceedings of the Second North American Conference on Biomechanics. Kingston, ON: Canadian Society for Biomechanics, Queen's University. Smith, G. (1989). Padding point extrapolation techniques for the butterworth digital filter. Journal of Biomechanics, 22, Winter, D.A. (1990). Biomechanics and motor control of human movement. Toronto, ON: Wiley. Acknowledgment For technical assistance, we wish to thank Dr. Tyseer Aboulnasr of the Department of Electrical Engineering, University of Ottawa.
Design and responses of Butterworth and critically damped digital filters
Journal of Electromyography and Kinesiology 13 (2003) 569 573 www.elsevier.com/locate/jelekin Technical note Design and responses of Butterworth and critically damped digital filters D. Gordon E. Robertson
More informationBCA 618 Biomechanics. Serdar Arıtan Hacettepe Üniversitesi. Spor Bilimleri Fakültesi. Biyomekanik Araştırma Grubu
BCA 618 Biomechanics Serdar Arıtan serdar.aritan@hacettepe.edu.tr Hacettepe Üniversitesi www.hacettepe.edu.tr Spor Bilimleri Fakültesi www.sbt.hacettepe.edu.tr Biyomekanik Araştırma Grubu www.biomech.hacettepe.edu.tr
More informationA Lower Transition Width FIR Filter & its Noise Removal Performance on an ECG Signal
American Journal of Engineering & Natural Sciences (AJENS) Volume, Issue 3, April 7 A Lower Transition Width FIR Filter & its Noise Removal Performance on an ECG Signal Israt Jahan Department of Information
More informationBiomechanical Instrumentation Considerations in Data Acquisition ÉCOLE DES SCIENCES DE L ACTIVITÉ PHYSIQUE SCHOOL OF HUMAN KINETICS
Biomechanical Instrumentation Considerations in Data Acquisition Data Acquisition in Biomechanics Why??? Describe and Understand a Phenomena Test a Theory Evaluate a condition/situation Data Acquisition
More informationBiosignal filtering and artifact rejection. Biosignal processing I, S Autumn 2017
Biosignal filtering and artifact rejection Biosignal processing I, 52273S Autumn 207 Motivation ) Artifact removal power line non-stationarity due to baseline variation muscle or eye movement artifacts
More informationInfinite Impulse Response Filters
6 Infinite Impulse Response Filters Ren Zhou In this chapter we introduce the analysis and design of infinite impulse response (IIR) digital filters that have the potential of sharp rolloffs (Tompkins
More informationThe Calculation of grms. QUALMARK: Accelerating Product Reliability WHITE PAPER
WHITE PAPER QUALMARK: Accelerating Product Reliability WWW.QUALMARK.COM 303.254.8800 by Neill Doertenbach The metric of grms is typically used to specify and compare the energy in repetitive shock vibration
More informationFill in the following worksheet-style pages. A colored pen or pencil works best. The procedure is:
14: ALIASING I. PRELAB FOR ALIASING LAB You might expect that to record a frequency of 4000 Hz you would have to sample at a rate of at least 4000 Hz. It turns out, however, that you actually have to sample
More informationHomework Assignment 07
Homework Assignment 07 Question 1 (Short Takes). 2 points each unless otherwise noted. 1. A single-pole op-amp has an open-loop low-frequency gain of A = 10 5 and an open loop, 3-dB frequency of 4 Hz.
More informationDesign of IIR Digital Filters with Flat Passband and Equiripple Stopband Responses
Electronics and Communications in Japan, Part 3, Vol. 84, No. 11, 2001 Translated from Denshi Joho Tsushin Gakkai Ronbunshi, Vol. J82-A, No. 3, March 1999, pp. 317 324 Design of IIR Digital Filters with
More informationActive Filter Design Techniques
Active Filter Design Techniques 16.1 Introduction What is a filter? A filter is a device that passes electric signals at certain frequencies or frequency ranges while preventing the passage of others.
More informationResponse spectrum Time history Power Spectral Density, PSD
A description is given of one way to implement an earthquake test where the test severities are specified by time histories. The test is done by using a biaxial computer aided servohydraulic test rig.
More informationActive Vibration Isolation of an Unbalanced Machine Tool Spindle
Active Vibration Isolation of an Unbalanced Machine Tool Spindle David. J. Hopkins, Paul Geraghty Lawrence Livermore National Laboratory 7000 East Ave, MS/L-792, Livermore, CA. 94550 Abstract Proper configurations
More informationFundamentals of Time- and Frequency-Domain Analysis of Signal-Averaged Electrocardiograms R. Martin Arthur, PhD
CORONARY ARTERY DISEASE, 2(1):13-17, 1991 1 Fundamentals of Time- and Frequency-Domain Analysis of Signal-Averaged Electrocardiograms R. Martin Arthur, PhD Keywords digital filters, Fourier transform,
More informationA New Method of Emission Measurement
A New Method of Emission Measurement Christoph Keller Institute of Power Transm. and High Voltage Technology University of Stuttgart, Germany ckeller@ieh.uni-stuttgart.de Kurt Feser Institute of Power
More informationLow Pass Filter Introduction
Low Pass Filter Introduction Basically, an electrical filter is a circuit that can be designed to modify, reshape or reject all unwanted frequencies of an electrical signal and accept or pass only those
More informationMeasurement System for Acoustic Absorption Using the Cepstrum Technique. Abstract. 1. Introduction
The 00 International Congress and Exposition on Noise Control Engineering Dearborn, MI, USA. August 9-, 00 Measurement System for Acoustic Absorption Using the Cepstrum Technique E.R. Green Roush Industries
More informationInterface Electronic Circuits
Lecture (5) Interface Electronic Circuits Part: 1 Prof. Kasim M. Al-Aubidy Philadelphia University-Jordan AMSS-MSc Prof. Kasim Al-Aubidy 1 Interface Circuits: An interface circuit is a signal conditioning
More informationLECTURER NOTE SMJE3163 DSP
LECTURER NOTE SMJE363 DSP (04/05-) ------------------------------------------------------------------------- Week3 IIR Filter Design -------------------------------------------------------------------------
More informationNH 67, Karur Trichy Highways, Puliyur C.F, Karur District DEPARTMENT OF INFORMATION TECHNOLOGY DIGITAL SIGNAL PROCESSING UNIT 3
NH 67, Karur Trichy Highways, Puliyur C.F, 639 114 Karur District DEPARTMENT OF INFORMATION TECHNOLOGY DIGITAL SIGNAL PROCESSING UNIT 3 IIR FILTER DESIGN Structure of IIR System design of Discrete time
More informationLaboratory Assignment 5 Amplitude Modulation
Laboratory Assignment 5 Amplitude Modulation PURPOSE In this assignment, you will explore the use of digital computers for the analysis, design, synthesis, and simulation of an amplitude modulation (AM)
More informationChapter 2 Analog-to-Digital Conversion...
Chapter... 5 This chapter examines general considerations for analog-to-digital converter (ADC) measurements. Discussed are the four basic ADC types, providing a general description of each while comparing
More informationSIGMA-DELTA CONVERTER
SIGMA-DELTA CONVERTER (1995: Pacífico R. Concetti Western A. Geophysical-Argentina) The Sigma-Delta A/D Converter is not new in electronic engineering since it has been previously used as part of many
More informationCHAPTER 6 INTRODUCTION TO SYSTEM IDENTIFICATION
CHAPTER 6 INTRODUCTION TO SYSTEM IDENTIFICATION Broadly speaking, system identification is the art and science of using measurements obtained from a system to characterize the system. The characterization
More informationEDL Group #3 Final Report - Surface Electromyograph System
EDL Group #3 Final Report - Surface Electromyograph System Group Members: Aakash Patil (07D07021), Jay Parikh (07D07019) INTRODUCTION The EMG signal measures electrical currents generated in muscles during
More informationDesign IIR Filters Using Cascaded Biquads
Design IIR Filters Using Cascaded Biquads This article shows how to implement a Butterworth IIR lowpass filter as a cascade of second-order IIR filters, or biquads. We ll derive how to calculate the coefficients
More informationOutline. Introduction to Biosignal Processing. Overview of Signals. Measurement Systems. -Filtering -Acquisition Systems (Quantisation and Sampling)
Outline Overview of Signals Measurement Systems -Filtering -Acquisition Systems (Quantisation and Sampling) Digital Filtering Design Frequency Domain Characterisations - Fourier Analysis - Power Spectral
More informationModule 1: Introduction to Experimental Techniques Lecture 2: Sources of error. The Lecture Contains: Sources of Error in Measurement
The Lecture Contains: Sources of Error in Measurement Signal-To-Noise Ratio Analog-to-Digital Conversion of Measurement Data A/D Conversion Digitalization Errors due to A/D Conversion file:///g /optical_measurement/lecture2/2_1.htm[5/7/2012
More informationDETERMINATION OF CUTTING FORCES USING A FLEXURE-BASED DYNAMOMETER: DECONVOLUTION OF STRUCTURAL DYNAMICS USING THE FREQUENCY RESPONSE FUNCTION
DETERMINATION OF CUTTING FORCES USING A FLEXURE-BASED DYNAMOMETER: DECONVOLUTION OF STRUCTURAL DYNAMICS USING THE FREQUENCY RESPONSE FUNCTION Michael F. Gomez and Tony L. Schmitz Department of Mechanical
More informationIntroduction to Op Amps By Russell Anderson, Burr-Brown Corp
Introduction to Op Amps By ussell Anderson, BurrBrown Corp Introduction Analog design can be intimidating. If your engineering talents have been focused in digital, software or even scientific fields,
More informationDepartment of Mechanical and Aerospace Engineering. MAE334 - Introduction to Instrumentation and Computers. Final Examination.
Name: Number: Department of Mechanical and Aerospace Engineering MAE334 - Introduction to Instrumentation and Computers Final Examination December 12, 2002 Closed Book and Notes 1. Be sure to fill in your
More informationIEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 50, NO. 12, DECEMBER
IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 50, NO. 12, DECEMBER 2002 1865 Transactions Letters Fast Initialization of Nyquist Echo Cancelers Using Circular Convolution Technique Minho Cheong, Student Member,
More informationCL Digital Control Kannan M. Moudgalya
CL 692 - Digital Control Kannan M. Moudgalya Department of Chemical Engineering Associate Faculty Member, Systems and Control IIT Bombay kannan@iitb.ac.in Autumn 2007 Digital Control 1 Kannan M. Moudgalya,
More information(i) Understanding of the characteristics of linear-phase finite impulse response (FIR) filters
FIR Filter Design Chapter Intended Learning Outcomes: (i) Understanding of the characteristics of linear-phase finite impulse response (FIR) filters (ii) Ability to design linear-phase FIR filters according
More informationHomework Assignment 06
Question 1 (2 points each unless noted otherwise) Homework Assignment 06 1. True or false: when transforming a circuit s diagram to a diagram of its small-signal model, we replace dc constant current sources
More informationUsing the isppac 80 Programmable Lowpass Filter IC
Using the isppac Programmable Lowpass Filter IC Introduction This application note describes the isppac, an In- System Programmable (ISP ) Analog Circuit from Lattice Semiconductor, and the filters that
More informationPart One. Efficient Digital Filters COPYRIGHTED MATERIAL
Part One Efficient Digital Filters COPYRIGHTED MATERIAL Chapter 1 Lost Knowledge Refound: Sharpened FIR Filters Matthew Donadio Night Kitchen Interactive What would you do in the following situation?
More information(i) Sine sweep (ii) Sine beat (iii) Time history (iv) Continuous sine
A description is given of one way to implement an earthquake test where the test severities are specified by the sine-beat method. The test is done by using a biaxial computer aided servohydraulic test
More informationElectric Circuit Theory
Electric Circuit Theory Nam Ki Min nkmin@korea.ac.kr 010-9419-2320 Chapter 15 Active Filter Circuits Nam Ki Min nkmin@korea.ac.kr 010-9419-2320 Contents and Objectives 3 Chapter Contents 15.1 First-Order
More informationELECTROMYOGRAPHY UNIT-4
ELECTROMYOGRAPHY UNIT-4 INTRODUCTION EMG is the study of muscle electrical signals. EMG is sometimes referred to as myoelectric activity. Muscle tissue conducts electrical potentials similar to the way
More informationPYKC 7 Feb 2019 EA2.3 Electronics 2 Lecture 13-1
In this lecture, we will look back on all the materials we have covered to date. Instead of going through previous lecture materials, I will focus on what you have learned in the laboratory sessions, going
More informationApplication Note 7. Digital Audio FIR Crossover. Highlights Importing Transducer Response Data FIR Window Functions FIR Approximation Methods
Application Note 7 App Note Application Note 7 Highlights Importing Transducer Response Data FIR Window Functions FIR Approximation Methods n Design Objective 3-Way Active Crossover 200Hz/2kHz Crossover
More informationFYS3240 PC-based instrumentation and microcontrollers. Signal sampling. Spring 2017 Lecture #5
FYS3240 PC-based instrumentation and microcontrollers Signal sampling Spring 2017 Lecture #5 Bekkeng, 30.01.2017 Content Aliasing Sampling Analog to Digital Conversion (ADC) Filtering Oversampling Triggering
More informationSHOCK AND VIBRATION RESPONSE SPECTRA COURSE Unit 17. Aliasing. Again, engineers collect accelerometer data in a variety of settings.
SHOCK AND VIBRATION RESPONSE SPECTRA COURSE Unit 17. Aliasing By Tom Irvine Email: tomirvine@aol.com Introduction Again, engineers collect accelerometer data in a variety of settings. Examples include:
More information(i) Understanding of the characteristics of linear-phase finite impulse response (FIR) filters
FIR Filter Design Chapter Intended Learning Outcomes: (i) Understanding of the characteristics of linear-phase finite impulse response (FIR) filters (ii) Ability to design linear-phase FIR filters according
More informationDesigning a 960 MHz CMOS LNA and Mixer using ADS. EE 5390 RFIC Design Michelle Montoya Alfredo Perez. April 15, 2004
Designing a 960 MHz CMOS LNA and Mixer using ADS EE 5390 RFIC Design Michelle Montoya Alfredo Perez April 15, 2004 The University of Texas at El Paso Dr Tim S. Yao ABSTRACT Two circuits satisfying the
More informationDigital Video and Audio Processing. Winter term 2002/ 2003 Computer-based exercises
Digital Video and Audio Processing Winter term 2002/ 2003 Computer-based exercises Rudolf Mester Institut für Angewandte Physik Johann Wolfgang Goethe-Universität Frankfurt am Main 6th November 2002 Chapter
More informationBasics of Digital Filtering
4 Basics of Digital Filtering Willis J. Tompkins and Pradeep Tagare In this chapter we introduce the concept of digital filtering and look at the advantages, disadvantages, and differences between analog
More informationPreliminary study of the vibration displacement measurement by using strain gauge
Songklanakarin J. Sci. Technol. 32 (5), 453-459, Sep. - Oct. 2010 Original Article Preliminary study of the vibration displacement measurement by using strain gauge Siripong Eamchaimongkol* Department
More informationDynamic thresholding for automated analysis of bobbin probe eddy current data
International Journal of Applied Electromagnetics and Mechanics 15 (2001/2002) 39 46 39 IOS Press Dynamic thresholding for automated analysis of bobbin probe eddy current data H. Shekhar, R. Polikar, P.
More informationKeysight Technologies Pulsed Antenna Measurements Using PNA Network Analyzers
Keysight Technologies Pulsed Antenna Measurements Using PNA Network Analyzers White Paper Abstract This paper presents advances in the instrumentation techniques that can be used for the measurement and
More informationFourier Theory & Practice, Part I: Theory (HP Product Note )
Fourier Theory & Practice, Part I: Theory (HP Product Note 54600-4) By: Robert Witte Hewlett-Packard Co. Introduction: This product note provides a brief review of Fourier theory, especially the unique
More informationSECTION 6: ROOT LOCUS DESIGN
SECTION 6: ROOT LOCUS DESIGN MAE 4421 Control of Aerospace & Mechanical Systems 2 Introduction Introduction 3 Consider the following unity feedback system 3 433 Assume A proportional controller Design
More informationResonance in Circuits
Resonance in Circuits Purpose: To map out the analogy between mechanical and electronic resonant systems To discover how relative phase depends on driving frequency To gain experience setting up circuits
More informationDesign of Accelerometer Pre-regulation Circuit and Performance Analysis of the Key Components
Sensors & Transducers 2013 by IFSA http://www.sensorsportal.com Design of Accelerometer Pre-regulation Circuit and Performance Analysis of the Key Components * Hou Zhuo, Wu Yongpeng, Zhen Guoyong National
More informationELEC-C5230 Digitaalisen signaalinkäsittelyn perusteet
ELEC-C5230 Digitaalisen signaalinkäsittelyn perusteet Lecture 10: Summary Taneli Riihonen 16.05.2016 Lecture 10 in Course Book Sanjit K. Mitra, Digital Signal Processing: A Computer-Based Approach, 4th
More informationAdvanced Measurements
Albaha University Faculty of Engineering Mechanical Engineering Department Lecture 9: Wheatstone Bridge and Filters Ossama Abouelatta o_abouelatta@yahoo.com Mechanical Engineering Department Faculty of
More informationActiveLowPassFilter -- Overview
ActiveLowPassFilter -- Overview OBJECTIVES: At the end of performing this experiment, learners would be able to: Describe the concept of active Low Pass Butterworth Filter Obtain the roll-off factor and
More informationCHAPTER 3 ANALOG SIGNAL CONDITIONING
19 CHAPTER 3 ANALOG SIGNAL CONDITIONING CHAPTER 3 ANALOG SIGNAL CONDITIONING 3.1 INTRODUCTION Amplifiers and Filters are the essential signal processing blocks of any analog signal conditioner. The characteristics
More informationAn Efficient Zero-Loss Technique for Data Compression of Long Fault Records
FAULT AND DISTURBANCE ANALYSIS CONFERENCE Arlington VA Nov. 5-8, 1996 An Efficient Zero-Loss Technique for Data Compression of Long Fault Records R.V. Jackson, G.W. Swift Alpha Power Technologies Winnipeg,
More informationBiosignal filtering and artifact rejection. Biosignal processing, S Autumn 2012
Biosignal filtering and artifact rejection Biosignal processing, 521273S Autumn 2012 Motivation 1) Artifact removal: for example power line non-stationarity due to baseline variation muscle or eye movement
More informationSection 5.2 Graphs of the Sine and Cosine Functions
Section 5.2 Graphs of the Sine and Cosine Functions We know from previously studying the periodicity of the trigonometric functions that the sine and cosine functions repeat themselves after 2 radians.
More informationBasic Signals and Systems
Chapter 2 Basic Signals and Systems A large part of this chapter is taken from: C.S. Burrus, J.H. McClellan, A.V. Oppenheim, T.W. Parks, R.W. Schafer, and H. W. Schüssler: Computer-based exercises for
More informationLab 12 Laboratory 12 Data Acquisition Required Special Equipment: 12.1 Objectives 12.2 Introduction 12.3 A/D basics
Laboratory 12 Data Acquisition Required Special Equipment: Computer with LabView Software National Instruments USB 6009 Data Acquisition Card 12.1 Objectives This lab demonstrates the basic principals
More informationLab 4 Digital Scope and Spectrum Analyzer
Lab 4 Digital Scope and Spectrum Analyzer Page 4.1 Lab 4 Digital Scope and Spectrum Analyzer Goals Review Starter files Interface a microphone and record sounds, Design and implement an analog HPF, LPF
More informationDIGITAL FILTERS. !! Finite Impulse Response (FIR) !! Infinite Impulse Response (IIR) !! Background. !! Matlab functions AGC DSP AGC DSP
DIGITAL FILTERS!! Finite Impulse Response (FIR)!! Infinite Impulse Response (IIR)!! Background!! Matlab functions 1!! Only the magnitude approximation problem!! Four basic types of ideal filters with magnitude
More informationSignals, sampling & filtering
Signals, sampling & filtering Scientific Computing Fall, 2018 Paul Gribble 1 Time domain representation of signals 1 2 Frequency domain representation of signals 2 3 Fast Fourier transform (FFT) 2 4 Sampling
More informationFOURIER analysis is a well-known method for nonparametric
386 IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, VOL. 54, NO. 1, FEBRUARY 2005 Resonator-Based Nonparametric Identification of Linear Systems László Sujbert, Member, IEEE, Gábor Péceli, Fellow,
More informationVeröffentlichungen am IKFF PIEZOELECTRIC TRAVELLING WAVE MOTORS GENERATING DIRECT LINEAR MOTION
Veröffentlichungen am IKFF PIEZOELECTRIC TRAVELLING WAVE MOTORS GENERATING DIRECT LINEAR MOTION M. Hermann, W. Schinköthe (IKFF) Beitrag zur Actuator 96 Bremen 26. - 28.06.96 Conference Proceedings, S.
More informationDSP Filter Design for Flexible Alternating Current Transmission Systems
DSP Filter Design for Flexible Alternating Current Transmission Systems O. Abarrategui Ranero 1, M.Gómez Perez 1, D.M. Larruskain Eskobal 1 1 Department of Electrical Engineering E.U.I.T.I.M.O.P., University
More informationAnalysis of Fast Fading in Wireless Communication Channels M.Siva Ganga Prasad 1, P.Siddaiah 1, L.Pratap Reddy 2, K.Lekha 1
International Journal of ISSN 0974-2107 Systems and Technologies IJST Vol.3, No.1, pp 139-145 KLEF 2010 Fading in Wireless Communication Channels M.Siva Ganga Prasad 1, P.Siddaiah 1, L.Pratap Reddy 2,
More informationMeasurement Techniques
Measurement Techniques Anders Sjöström Juan Negreira Montero Department of Construction Sciences. Division of Engineering Acoustics. Lund University Disposition Introduction Errors in Measurements Signals
More informationDepartment of Mechanical and Aerospace Engineering. MAE334 - Introduction to Instrumentation and Computers. Final Examination.
Name: Number: Department of Mechanical and Aerospace Engineering MAE334 - Introduction to Instrumentation and Computers Final Examination December 12, 2003 Closed Book and Notes 1. Be sure to fill in your
More informationValidation & Analysis of Complex Serial Bus Link Models
Validation & Analysis of Complex Serial Bus Link Models Version 1.0 John Pickerd, Tektronix, Inc John.J.Pickerd@Tek.com 503-627-5122 Kan Tan, Tektronix, Inc Kan.Tan@Tektronix.com 503-627-2049 Abstract
More informationDIGITAL FILTERING OF MULTIPLE ANALOG CHANNELS
DIGITAL FILTERING OF MULTIPLE ANALOG CHANNELS Item Type text; Proceedings Authors Hicks, William T. Publisher International Foundation for Telemetering Journal International Telemetering Conference Proceedings
More informationPHYS225 Lecture 15. Electronic Circuits
PHYS225 Lecture 15 Electronic Circuits Last lecture Difference amplifier Differential input; single output Good CMRR, accurate gain, moderate input impedance Instrumentation amplifier Differential input;
More informationSignal Processing for Digitizers
Signal Processing for Digitizers Modular digitizers allow accurate, high resolution data acquisition that can be quickly transferred to a host computer. Signal processing functions, applied in the digitizer
More informationA Low-Cost Programmable Arbitrary Function Generator for Educational Environment
Paper ID #5740 A Low-Cost Programmable Arbitrary Function Generator for Educational Environment Mr. Mani Dargahi Fadaei, Azad University Mani Dargahi Fadaei received B.S. in electrical engineering from
More informationSHAKER TABLE SEISMIC TESTING OF EQUIPMENT USING HISTORICAL STRONG MOTION DATA SCALED TO SATISFY A SHOCK RESPONSE SPECTRUM
SHAKER TABLE SEISMIC TESTING OF EQUIPMENT USING HISTORICAL STRONG MOTION DATA SCALED TO SATISFY A SHOCK RESPONSE SPECTRUM By Tom Irvine Email: tomirvine@aol.com May 6, 29. The purpose of this paper is
More informationThis manuscript was the basis for the article A Refresher Course in Control Theory printed in Machine Design, September 9, 1999.
This manuscript was the basis for the article A Refresher Course in Control Theory printed in Machine Design, September 9, 1999. Use Control Theory to Improve Servo Performance George Ellis Introduction
More informationA.C. FILTER NETWORKS. Learning Objectives
C H A P T E 17 Learning Objectives Introduction Applications Different Types of Filters Octaves and Decades of Frequency Decibel System alue of 1 db Low-Pass C Filter Other Types of Low-Pass Filters Low-Pass
More informationImproving ECG Signal using Nuttall Window-Based FIR Filter
International Journal of Precious Engineering Research and Applications (IJPERA) ISSN (Online): 2456-2734 Volume 2 Issue 5 ǁ November 217 ǁ PP. 17-22 V. O. Mmeremikwu 1, C. B. Mbachu 2 and J. P. Iloh 3
More informationTest Your Understanding
074 Part 2 Analog Electronics EXEISE POBLEM Ex 5.3: For the switched-capacitor circuit in Figure 5.3b), the parameters are: = 30 pf, 2 = 5pF, and F = 2 pf. The clock frequency is 00 khz. Determine the
More informationENGINEERING STAFF REPORT. The JBL Model L40 Loudspeaker System. Mark R. Gander, Design Engineer
James B Lansing Sound, Inc, 8500 Balboa Boulevard, Northridge, California 91329 USA ENGINEERING STAFF REPORT The JBL Model L40 Loudspeaker System Author: Mark R. Gander, Design Engineer ENGINEERING STAFF
More informationAD8232 EVALUATION BOARD DOCUMENTATION
One Technology Way P.O. Box 9106 Norwood, MA 02062-9106 Tel: 781.329.4700 Fax: 781.461.3113 www.analog.com AD8232 EVALUATION BOARD DOCUMENTATION FEATURES Ready to use Heart Rate Monitor (HRM) Front end
More informationCHAPTER 7 INTERFERENCE CANCELLATION IN EMG SIGNAL
131 CHAPTER 7 INTERFERENCE CANCELLATION IN EMG SIGNAL 7.1 INTRODUCTION Electromyogram (EMG) is the electrical activity of the activated motor units in muscle. The EMG signal resembles a zero mean random
More informationChanging the sampling rate
Noise Lecture 3 Finally you should be aware of the Nyquist rate when you re designing systems. First of all you must know your system and the limitations, e.g. decreasing sampling rate in the speech transfer
More informationTheoretical 1 Bit A/D Converter
Acquisition 16.1 Chapter 4 - Acquisition D/A converter (or DAC): Digital to Analog converters are used to map a finite number of values onto a physical output range (usually a ) A/D converter (or ADC):
More informationLaboratory Assignment 1 Sampling Phenomena
1 Main Topics Signal Acquisition Audio Processing Aliasing, Anti-Aliasing Filters Laboratory Assignment 1 Sampling Phenomena 2.171 Analysis and Design of Digital Control Systems Digital Filter Design and
More informationTexas Components - Data Sheet. The TX53G1 is an extremely rugged, low distortion, wide dynamic range sensor. suspending Fluid.
Texas Components - Data Sheet AN004 REV A 08/30/99 DESCRIPTION and CHARACTERISTICS of the TX53G1 HIGH PERFORMANCE GEOPHONE The TX53G1 is an extremely rugged, low distortion, wide dynamic range sensor.
More informationAn active filter offers the following advantages over a passive filter:
ACTIVE FILTERS An electric filter is often a frequency-selective circuit that passes a specified band of frequencies and blocks or attenuates signals of frequencies outside this band. Filters may be classified
More informationSubtractive Synthesis without Filters
Subtractive Synthesis without Filters John Lazzaro and John Wawrzynek Computer Science Division UC Berkeley lazzaro@cs.berkeley.edu, johnw@cs.berkeley.edu 1. Introduction The earliest commercially successful
More informationLab 2: Designing a Low Pass Filter
Lab 2: Designing a Low Pass Filter In this lab we will be using a low pass filter to filter the signal from an Infra Red (IR) sensor. The IR sensor will be connected to the Arduino and Matlab will be used
More informationSignal Processing. Naureen Ghani. December 9, 2017
Signal Processing Naureen Ghani December 9, 27 Introduction Signal processing is used to enhance signal components in noisy measurements. It is especially important in analyzing time-series data in neuroscience.
More informationPulse Code Modulation (PCM)
Project Title: e-laboratories for Physics and Engineering Education Tempus Project: contract # 517102-TEMPUS-1-2011-1-SE-TEMPUS-JPCR 1. Experiment Category: Electrical Engineering >> Communications 2.
More informationLecture 2 Analog circuits. Seeing the light..
Lecture 2 Analog circuits Seeing the light.. I t IR light V1 9V +V IR detection Noise sources: Electrical (60Hz, 120Hz, 180Hz.) Other electrical IR from lights IR from cameras (autofocus) Visible light
More informationDigital Signal Processing of Speech for the Hearing Impaired
Digital Signal Processing of Speech for the Hearing Impaired N. Magotra, F. Livingston, S. Savadatti, S. Kamath Texas Instruments Incorporated 12203 Southwest Freeway Stafford TX 77477 Abstract This paper
More informationChapter 7. Introduction. Analog Signal and Discrete Time Series. Sampling, Digital Devices, and Data Acquisition
Chapter 7 Sampling, Digital Devices, and Data Acquisition Material from Theory and Design for Mechanical Measurements; Figliola, Third Edition Introduction Integrating analog electrical transducers with
More informationDo all accelerometers behave the same? Meggitt-Endevco, Anthony Chu
Do all accelerometers behave the same? Meggitt-Endevco, Anthony Chu A leader in design and manufacturing of accelerometers & pressure transducers, Meggitt Endevco strives to deliver product innovations
More informationDual FET-Input, Low Distortion OPERATIONAL AMPLIFIER
www.burr-brown.com/databook/.html Dual FET-Input, Low Distortion OPERATIONAL AMPLIFIER FEATURES LOW DISTORTION:.3% at khz LOW NOISE: nv/ Hz HIGH SLEW RATE: 25V/µs WIDE GAIN-BANDWIDTH: MHz UNITY-GAIN STABLE
More information