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Issue 1, Volume 5,
January 2008
Title of the Paper: Development of
Autonomous and Active Monitoring Fish Robots for Water Pollution Using GPS
and Ubiquitous Sensor Networks
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Authors: Seung
Y. Na, Daejung Shin, Jin Y. Kim, Yong-Gwan Won, Bae-Ho
Lee
Abstract: We introduce and develop an autonomous monitoring system for water
pollution that searches the sources of water pollution and makes measurements
of relevant data using a fish robot. Fish robots search actively by
themselves and monitor various areas in a real-time mode using GPS receivers,
ubiquitous sensor networks and directional sensors. A fish robot has three
microcontrollers which provide full functions, for example, motor operations
for the sw Localization imming
of a fish robot, analog sensor data acquisition including temperature and
infrared distance sensors, decoding GPS information, counting the time of
sonar in ultrasound sensors and a directional sensor, collecting information
of water pollution measurement sensors from Vernier
Labpro, and communications. A fish robot swims
autonomously in predefined areas and collects the water pollution indexes.
Collected information by a fish robot is sent to data collecting nodes by USN
motes and Bluetooth, and the data are accessible on the Internet by Ethernet
devices.
Keywords: Fish Robot,
Water Pollution, Autonomous Tracking System, Active monitoring
Title of the Paper: Efficient
Implementation of Fault-Tolerant Data Structures in Embedded Control Software
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Authors: Michael Short, Michael Schwarz, Josef Boercsoek
Abstract: This paper presents a methodology and small software library which
is intended to reduce the impact of transient data errors that may affect the
software executing on commercial-of-the-shelf (COTS) embedded processors. The
methodology involves duplication of data in disparate areas of memory
(referred to as “mirror arrays”), and the complexity of the processing
required to manage these areas is hidden by means of a library exporting new
basic data types. Results are reported from three case studies in which the
library was employed (a matrix multiplication program, a list-sorting program
and a real-time control application): the findings obtained suggest that the
methodology is highly effective in the presence of memory errors, the code
changes required in order to use the library are very limited, and the impact
on code readability is minimal.
Keywords: Software Fault Tolerance, Embedded Systems, Critical Systems.
Issue 2, Volume 5,
February 2008
Title of the Paper: Operational
Amplifiers in Discrete Time Control Systems: Influence of the Rail-to-Rail
Feature on their Performance
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Authors: Alvaro Llaria,
Jaime Jimenez, Unai Bidarte, Octavian Curea
Abstract: One of the usual features that an operational amplifier may offer is
the rail-to-rail capability. This means that its output range is equal to the
power voltages (positive and negative or zero) without any offset. In some
cases this feature does not concern with the performance of the system
because it does not operate in the limits of the output range or the offsets
are small enough not to care about them. Nevertheless, when an accurate instrumentation
system must be used, as in this article, the rail-to-rail capability is
crucial not to degrade the performance. For instance, the circuit may loose
linearity and resolution if the operational amplifiers are not adequate. In
our case, a circuit to perform some discrete time control algorithms needed a
maximum output range for the system to work properly. With the initial
operational amplifiers, the performance was not adequate. After setting
rail-to-rail ones the problem has been resolved.
Keywords: Operational
amplifier, rail-to-rail, output range, linearity, RST discrete time
controller.
Title of the Paper: Examination of
Non-Uniform Distribution of Current on Worst-Case Crosstalk Noise for
Distributed RLC Interconnect
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Authors:
HJ
Kadim
Abstract: Considering circuit designs at the deep sub-micron level, the more
that interconnect wires of small cross section are packed closer together,
coupled with longer length of interconnect and an increase in the number of
layers of interconnect may cause different parts of an interconnect line to
experience a varying degree of coupling effect from other interconnects, with
the consequent variation in the induced-current across the interconnect. An
analytical model to examine the effect of non-uniform distribution of current
on the mutual inductance and capacitance between on-chip interconnects is
presented.
Keywords: Interconnect,
crosstalk, noise, distributed RLC
Title of the Paper: Adaptive Wiener
Filter Based Numerical Filter with an Application to Beam Position Monitoring
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Authors: Khuanjai
Nachaiyaphum, Sarawut Sujitjorn, Supakorn Rugmai
Abstract: This article proposes a numerical filter having an adaptive Wiener
filter (AWF) as its main component. It presents detailed investigation of the
performances of the Savitzky-Golay filter (SGF) and
the AWF. As a result, the AWF is superior to the SGF in terms of less
distortion of the filtered waveform. The desired signal fed to the AWF can be
selectively generated by using a Butterworth filter, a Savitzky-Golay
filter, and a downloaded waveform, respectively. User can easily choose
filter’s parameters to suit their applications via a user-interface module.
The proposed filter is simple, rapidly computable, and efficient to suppress
noise. An application to the Siam Photon Source (Synchrotron Radiation Unit
on Thailand)
is also described. The filters coded in C are listed in the appendices and
downloadable from our web site.
Keywords: noise, adaptive
Wiener filter, Butterworth filter, Savitzky-Golay
filter, Siam Photon Source
Issue 3, Volume 5,
March 2008
Special Issue: Real-time Applications with 3D Sensors
Guest Editor: Prof. Marius Otesteanu
Title of the Paper: 3D Image Sensors,
an Overview
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Authors: Marius Otesteanu, Vasile Gui
Abstract: We briefly introduce the current state in the most widely used 3D
image sensors in computer vision today. Passive and active sensing methods
are discussed, with highlight on difficult computer vision problems that can
be avoided by using active methods. Active optoelectronic imaging methods
like time of flight, interferometry and
triangulation are presented. The 3D image processing applications included in
this issue are reviewed and some conclusions drown.
Title of the Paper: 3D Avatar Modeling
and Transmission using Cylinder Mapping
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Authors: Shin-Ichiro Takahashi, Ishtiaq Rasool Khan, Masahiro
Okuda, Masaaki Ikehara
Abstract: In this paper, we propose a real time 3D imaging system. Existing
techniques for construction of 3D models require multiple cameras and complex
calculations. In our proposed system, the 3D shape is captured by integrating
multiple range images obtained simultaneously from different directions. It
can accomplish the real time processing by generating the range images
quickly and continuously. Moreover, the obtained 3D shape is treated as ”Point Cloud”, and therefore, the connectivity
information of vertices and the calculation of connection topology become
unnecessary. Giving importance to transmission efficiency is the advantage of
our system. The obtained 3D shape is transmitted to the remote location, and
it is reconstructed and depicted immediately. By repeating this procedure
continuously, a 3D sequence can be generated in real time. The 3D shape is
constructed by integration of multiple range images, causing overlap and
annoying artifacts between adjacent images. We apply a cylindrical method to
each frame of the 3D sequence to get rid of the artifact and improve the
image quality. Our algorithm can remove the invalid points quickly and
efficiently, and can be implemented in real time.
Keywords: Real Time
Systems, Stereo Vision, Point Cloud
Title of the Paper: Real Time
Representation of 3D Sensor Depth Images
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Authors: I.
Jivet, A. Brindusescu
Abstract: The paper presents a representation model for 3D sensors depth
images for use in independent sub system real time action. Field of view
depth images obtained with recently developed CMOS 3D sensors are analyzed on
their usability in real time perception applications. Based on the
characteristic features of the 3D depth image an abstract model with an
associated segmented representation is proposed. The objective of the global
segmentation method proposed is real time scene perception. The segmentation
robustness and the computation cost are the central constraints considered.
Classic segmentation methods in use are used as reference since the use pixel
or edge criteria have been found insufficiently efficient due to their
intensive processing needs and susceptibility to local noise. A model of the
depth image in terms of object area and mean center location is proposed as a
real time local depth image representation. The results of
the use of the proposed model in independent action oriented applications is
also presented. The representation method proposed is analyzed in its
performance in terms of estimated computation time and semantic relevance for
the sample applications.
Keywords: 3D sensor depth
image, segmentation, real time perception, action oriented sensor data model.
modelvi1vtemp
Title of the Paper: A New Morphological
Image Segmentation with Application in 3D Echographic
Images
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Authors: Mihaela
Lascu, Dan Lascu
Abstract: This paper reviews ultrasound segmentation methods, in a broad
sense, focusing on techniques developed for medical ultrasound images.
Segmenting abnormal from normal myocardium using highfrequency
intracardiac echocardiography (ICE) the 3D
real-time images present new challenges for image processing in LabVIEW. Gray-level intensity and texture features of ICE
images of myocardium with the same structural/perfusion properties differ.
There are significant limitation conflicts with the existing segmentation
techniques. The novelty of this paper consists of a new seeded region growing
method to overcome the limitations of the existing segmentation techniques.
The segmentation techniques are implemented using graphical programming LabVIEW and Vision. We use three criteria for region
growing control: First, each voxel is merged into
the globally closest region in the multifeature
space. Second structural similarity is introduced to overcome the problem
that myocardial tissue, despite having the same property, may be segmented
into several different regions using existing segmentation methods. Third
equal opportunity competence criterion is employed making results independent
of processing order. This novel watershed segmentation method is applied to
in vivo intracardiac ultrasound images using
pathology as the reference method for the ground truth. The corresponding
results demonstrate that this method is reliable and effective.
Keywords: ultrasound,
echocardiography, graphical programming, watershed transform, watershed
segmentation, image processing, LabVIEW, Vision.
Title of the Paper: Fast Object
Localization with Real Time 3D Laser
Range Sensor Simulation
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Authors: Kay Boehnke
Abstract: 3D laser range sensors provide range data of objects in a scene.
Most of the known approaches for object recognition and localization in range
data try to extract features and determine the position of the object from
this information. In opposite we create a virtual scene, make a virtual range
image with a virtual 3D laser range sensor and compare the result with range
data of the real 3D laser range sensor. This idea is integrated in a system
for automated robotic bin picking. Our simulation process is combined with a
hierarchical registration process using the iterative closest point algorithm
and Progressive meshes to refine our simulation results.
Keywords: 3D laser range
sensors, Real time object localization, Iterative Closest Points, Surface
registration, Progressive Mesh, Robotic bin picking
Title of the Paper: A Flexible
Multi-Sensor Positioning System for Industrial Robots
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Authors: Philipp Roebrock
Abstract: This paper offers an approach for a sensor-based robot positioning
system which solves the problem of positioning the tool of an industrial
robot relative to a work object for a subsequent assembly or application in
the same way as it was done once during setup with a reference work object.
The approach takes sensors as abstract data sources and is therefore able to
use different kinds of sensors at the same time to fulfill its task. The
proposed solution focusses on a flexible system
that suits the needs of the industry in respect of good maintainability, good
robustness and high accuracy.
Keywords: Visual Servoing, Robot Positioning System, Multi-Sensor System
Issue 4, Volume 5,
April 2008
Title of the Paper: Oxide Charges
Densities Determination Using Charge-Pumping Technique With BTS in MOS
Structures
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Authors: Hamid
Bentarzi, Abdelkader Zitouni, Youces Kribes
Abstract: A New electrical method, using charge-pumping (CP) technique under
bias thermal stress (BTS), has been described in this paper. This technique
is based on the charge-pumping measurement which in turn used to extract the
flat-band voltage before and after an applied bias voltage at high temperature.
The obtained flat band voltage shift, that is due to redistribution of the
mobile ionic charges, or to generation of the oxide trapped charge or both,
may be used to determine their densities.
Keywords: Oxide charges,
charge pumping technique, bias thermal stress technique, flat-band voltage,
oxide charge, mobile ionic charge density, oxide trapped charge density.
Title of the Paper: Current-Mode
Filters Advanced Synthesis Methods, Based on Intermediate Transfer Function
Algorithm
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Authors: Elena Doicaru,
Mircea Bodea, Claudius
Dan
Abstract: In this paper are presented two current mode techniques for
low-voltage, continuous-time, analogue filter
implementation. The first presented technique is adequate for very low power
application and is based on a translinear approach.
The second presented technique is adequate for high frequency application. In
the paper, firstly, the state-space description and the used synthesis
techniques of current-mode filters are presented. Then the two different
current-mode integrators are presented and analyzed. Finally, as a test
vehicle for the proposed techniques, two low voltage,
third order, continuous-time filters, for low power applications structure
implementation are described and analyzed.
Keywords: Analogue signal
processing circuits, CMOS analogue filters, low power and voltage circuits.
Title of the Paper: Visual Motorcycle
Detection and Tracking Algorithms
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Authors: Min-Yu Ku, Chung-Cheng Chiu,
Hung-Tsung Chen, Shun-Huang Hong
Abstract: Although the motorcycle is a popular and convenient means of
transportation, it is difficult for researchers in intelligent transportation
systems to detect and recognize, and there has been little published work on
the subject. This paper describes a real-time motorcycle monitoring system to
detect, recognize, and track moving motorcycles in sequences of traffic
images. Because a motorcycle may overlap other vehicles in some image
sequences, the system proposes an occlusive detection and segmentation method
to separate and identify motorcycles. Since motorcycle riders in many
countries must wear helmets, helmet detection and search methods are used to
ensure that a helmet exists on the moving object identified as a motorcycle.
The performance of the proposed system was evaluated using test video data
collected under various weather and lighting
conditions. Experimental results show that the proposed method is effective
for traffic images captured any time of the day or night with an average
correct motorcycle detection rate of greater than 90% under various weather
conditions.
Keywords: Motorcycle
detection, Visual, Tracking, Occlusion, Segmentation, Traffic monitoring.
Title of the Paper: Design and
Performance Analysis of a Reconfigurable Arbiter
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Authors: Yu-Jung Huang, Ching-Mai Ko, Hsien-Chiao Teng
Abstract: This paper presents the design and performance analysis of an
arbiter with a hybrid arbitration algorithm. The hybrid arbitration algorithm
contains static fixed priority algorithm in conjunction with dynamic
algorithm to gain better system performance is described. The performance
analysis for the various combinations of the arbitration algorithms under
different traffic loads is simulated. The results indicate a better
performance can be achieved as compared with the traditional arbitration
assignment scheme. Based on the performance analysis, the hybrid arbitration
can be custom-tuned to meet the design requirements. The implementation of
the arbiter with hybrid arbitration scheme for system on chip applications is
also explained. The reconfigurable arbiter was implemented by FPGA and
synthesized by Synopsys Design Complier with a TSMC 0.18 μm
cell library. In addition, the power analysis of the reconfigurable arbiter
at various arbitration states is reported. The reconfigurable arbiter can be
custom-tuned to obtain high bandwidth utilization, low latency, and power
effective for on-chip bus communication.
Keywords: Arbiter,
Reconfigurable, System-on-chip, Arbitration Algorithm, FPGA, AMBA
Title of the Paper: Real -Time 3D
Echocardiography Processing
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Authors: Mihaela
Lascu, Dan Lascu
Abstract: Real-time 3-D echocardiography (RT3DE) opens up the possibility of
interactive, fast 3-D analysis of cardiac anatomy and function. However,
estimation of 3-D parameters using only 2-D images is based on geometric
assumptions about the shape of the heart and is dependent on the exact
position of the scanning plane. This produces significant errors and interobserver variability. First attempts to acquire 3-D echocardiographic datasets used freehand scanning.
However, freehand echocardiography requires several acquisitions and the
addition of 3-D localizing hardware, and can be affected by patient
breathing, patient movement, and irregular cardiac cycles. As an alternative
to freehand echocardiography, systems that automatically move the ultrasound
transducer in a controlled way have been developed alternatives that include
fan-like scanning and stepwise rotational scanning. However, at the present
time its quantitative power cannot be fully exploited due to the limited
quality of the images. In this paper are implemented LabVIEW
(Laboratory Virtual Instrumentation Engineering Workbench) algorithms that
improve the quality of the image. For the beginning we realise
histogram, create line profile, calculate measurement statistics associated
with a region of interest in the image, realise 3D
real-time view and modify the brightness, contrast and gamma of the acquired
image. Finally we implement in LabVIEW edge
detection and smoothing averaging.
Keywords:
Echocardiography, image acquisition, image processing, graphical programming,
3D real-time view, LabVIEW, Vision.
Title of the Paper: Modeling and
Simulation of RF MEMS devices
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Authors: Rajesh S. Pande, Rajendra M. Patrikar
Abstract: A stable, device specific, multiple energy domain and multi scale
simulation tool for Radio Frequency (RF) MicroElectroMechanicalSystems
(MEMS) devices is developed. A structured design methodology is adopted for
design and optimization of RF MEMS shunt switch and MEMS inductor. The
Computer Aided Design (CAD) tool incorporates physical parameters such as
surface roughness. An electromechanical model of the RF MEMS shunt switch is
solved by a numerical technique based on the iterative Finite Element Method
(FEM). The electrical properties such as capacitance and electric field are
obtained. The algorithm to extract inductor is based on solution of Laplace equation by FEM followed by current density
computation. The energy of resulting magnetic field is estimated by Monte Carlo sampling. The tool also generates CIF
(Caltech Intermediate Form) net list necessary for planar mask lay out. The
tool analyzes the impact of surface roughness and also does thermal analysis.
These are useful for understanding reliability and failure mechanisms of RF
MEMS components.
Keywords: RF, MEMS, CAD,
EDA, FEM, surface roughness
Issue 5, Volume 5,
May 2008
Title of the Paper: Computational
Techniques to Solve Electromagnetic Problems by Using FEM
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Authors: N. Fusun
Serteller, Dursun
Ustundag
Abstract: Numerical
modeling is nowadays an essential tool for all researchers involved with the
field of electrical, mechanical engineering, physics and etc. The object of
this paper is to provide a clear, easy and understandable study on FEM
(finite element method) using MATLAB and MATHEMATICA, which both provide
powerful support to solve large equations. 1D and 2D FEM solutions are
studied on electromagnetic (EM) field distribution which is one of the
essential parts of electrical engineering. The results from the two different
programs were compared with those obtained by using the finite difference
method (FD). Computer programs and formulations of the finite element
technique have been constructed to make the concept more understandable and
explicit for engineering students and practicing engineers.
Keywords: MATLAB, Mathematica, FEM,
FD, Electrostatic Analysis.
Title of the Paper: The Analysis of
Thermal Behavior in Ferromagnetic Core Using Boundary Element Method
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Authors: Fusun
Serteller
Abstract: This study presents a method
for computing thermal properties of an actuator and compares various magnetic
materials. The two-dimensional heat conduction problem is studied using the
boundary element method (BEM) with Poisson equivalence. Linear elements are
used in the solution procedure. The temperature distribution in the
ferromagnetic body is evaluated under stationary condition. The numerical
results have been compared with the results of the finite element method
(FEM). Numerical experiments have been carried out on soft ferromagnetic
materials such as silicon steel iron; mild iron; pure iron and amorf and results the temperature distribution are
graphed.
Keywords: Boundary Element Method, ferromagnetic materials,
Finite Element Method, thermal analysis, actuator.
Title of the Paper: Interactive Command
Language for OrCAD PSpice
via Simulation Manager and its Utilization for Special Simulations in Electrical Engineering
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Authors: Dalibor
Biolek, Jaroslav Kadlec, Viera Biolkova, Zdenek Kolka
Abstract: The Interactive Command Language (ICL) significantly extends the
simulation performance of several programs based on SPICE3 standard for the
analysis of electrical networks in the so-called sequential mode, when the
relatively independent tasks are run consecutively with a possibility of data
exchange. However, the ICL is not implemented in the well-known OrCAD PSpice
simulation program. The paper describes a conception of the so-called PSpice
Simulation Manager (PSiM). This program implements the ICL in OrCad PSpice.
PSiM is an independently executable program which controls the OrCad PSpice,
enabling its operation in sequential mode. A powerful programming language
also enables iterative runs within the conditional loops, which can be
utilized e.g. for optimization. Concrete demonstrations of PSiM performance
for circuit optimization and AC analysis of switched networks are included at
the conclusion.
Keywords: PSpice, PSiM, simulation, analysis, circuit
Issue
6, Volume 5,
June 2008
Special Issue:
Modern Circuit Components for Analogue Signal
Processing and their Applications
Guest Editor: Prof. Dalibor Biolek
Editorial
Title of the Paper: CMOS Realization of
the Operational Mirror Amplifier
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Authors:
A. Soltan, A. H. Madian, A. M. Soliman
Abstract: The design of a CMOS operational mirrored amplifier (OMA) suitable
for high frequency applications is proposed. The CMOS operational mirrored
amplifier is developed using class AB operational amplifier and two current
mirrors. To obtain a wide bandwidth and high stability, HF feedforward
techniques have been used. These techniques made the proposed circuit suitable
for continuous – time analog signal processing. Simulation results for the
proposed CMOS operational mirror amplifier circuit using PSpice are presented.
Also, a performance comparison with pervious realization using BJT is given.
Keywords: Operational mirror amplifier, Nullor, Nullator, Darlington pair,
CMOS, operational floating amplifier
Title of the Paper: BiCMOS
Current-Controlled Current Feedback Amplifier (CC-CFA) and Its Applications
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Authors:
Montree Siripruchyanun, Chaiyan Chanapromma, Phamorn Silapan, Winai Jaikla
Abstract: This paper introduces a modified version of current feedback
amplifier (CFA), called current controlled current feedback amplifier
(CC-CFA), to extend usabilities of this active element in terms of electronic
control-abilities and simpler circuit description of the element’s
applications. This modified element was realized by using a BiCMOS standard
technology to reduce offset error phenomenon, the design configuration is
systematically explained. The performances have been proven through PSPICE
which is accordance with theoretical anticipations. In addition, application
examples for a current-mode multiplier/divider, oscillator, grounded
inductance simulator, filters, and amplifiers are included. The results are
confirmed that the electrical characteristics are electronically tunable.
Keywords: CC-CFA, Current-mode, Voltage-mode, Filter, Oscillator, Inductance
simulator, Multiplier
Title of the Paper: Configurable Analog
Block based on CFOA and its Application
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Authors:
Ahmed H. Madian, Soliman A. Mahmoud, Ahmed M. Soliman
Abstract: A proposed configurable analog block (CAB) is presented, simulated
and analyzed. The CAB consists of a CMOS current feedback operational
amplifier (CFOA), presented by the authors, as the main active block,
programmable four MOS nonlinearity cancellation cells, programmable capacitor
array and MOSFET switches. Using the CABs, the universal field programmable
analog array (FPAA) could be constructed, which can realize many
signal-processing functions including variable gain amplifiers, filters. To
show the reliability of the proposed CAB, a low-pass, band-pass, high-pass
filter structure has been realized using the proposed CAB.
Keywords: CMOS, current feedback operational amplifier, configurable analog
blocks, nonlinearity cancellation, filters
Title of the Paper: Comparative
Performance of Low Voltage CMOS - CFOA Suitable for Analog VLSI
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Authors:
R. K. Nagaria, M. Gopi Krishna, Rakesh Kr. Singh
Abstract: The performance of the low voltage CMOS-CFOA with different aspect
ratios is presented in this paper.The solution works using a low supply
voltage and provides a wide input/output swing as well as a high current
driving capability. The circuit allows almost a rail-to-rail input and output
operation and it provides high driving capabilities. The CFOA is operating at
supply voltages of ± 0.75V.The circuit exhibits better than 100 MHz bandwidth
and ± 1mA current drive capability. The CMOS CFOA is simulated in Pspice using
0.35μm and 0.25μm TSMC technology. The circuit exhibits better performance
particularly greater bandwidth and low power consumption with improved dynamic
range after resizing the aspect ratios using 0.35μm to 0.25μm CMOS technology.
The simulation results are promising and the resized structure is suitable for
analog/mixed-mode VLSI design.
Keywords: CMOS CFOA, High performance, Low Voltage, Low Power
Title of the Paper: On the New Design of
CFA based Voltage Controlled Integrator/ Differentiator Suitable for Analog
Signal Processing
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Authors:
R. K. Nagaria
Abstract: Some new active Voltage Controlled RC integrator and differentiator
circuit realizations, with both single and differential input capabilities,
using a few passive components and a current feedback amplifier (CFA) device,
are proposed. A multiplier (ICL - 8013) element has been appropriately
utilized in the feed forward / feedback connection to obtain electronic tuning
of the time constant (τo) by the d.c. control voltage (Vc) of the multiplier.
Experimental result on wave processing had been verified in the frequency
range of 50 KHz ? 300 KHz. The active τo sensitivities in the event of
non-ideal CFA are shown to be extremely low.
Keywords: Current feedback amplifier, voltage controlled
integrator/differentiator (VCI/VCD)
Title of the Paper: Current-Mode Filters
with High Output Impedance and Employing Only Grounded Components
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Authors:
Sudhanshu Maheshwari
Abstract: This paper presents several new current-mode second order filters
suited for low-Q applications. The new circuits employ only grounded
components and possess high output impedance, ideal for current-mode
cascading. Effects of non-idealities and parasitics are also discussed. The
new circuits possess good active and passive sensitivity performance. PSPICE
simulation results are included for verification of proposed circuits.
Keywords: Current-mode, analog signal processing, active filter, differential
voltage current conveyor
Title of the Paper: High Performance
Voltage – Mode Multifunction Filter with Minimum Component Count
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Authors:
Sudhanshu Maheshwari
Abstract: This paper presents a new second order multifunction filter using
one active element, requiring only ‘twelve’ CMOS transistors, and four passive
elements. The proposed circuit realizes voltage-mode low-pass, high-pass and
band-pass functions with the advantages of minimum component count structure,
high Q possibility, and high frequency potential. The proposed circuit is
verified through PSPICE simulation results.
Keywords: Analog filtering, multifunction filters, low cost, differential
voltage current conveyor
Title of the Paper: Single-CDTA (Current
Differencing Transconductance Amplifier) Current-Mode Biquad Revisited
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Authors:
Dalibor Biolek, Viera Biolkova, Zdenek Kolka
Abstract: This paper presents a current-mode (CM) second-order filter,
employing one so-called “Z Copy –Current Differencing Transconductance
Amplifier” (ZC-CDTA), two grounded capacitors, and one virtually grounded
resistor. The filter provides two current outputs of low-pass (LP) and
band-pass (BP) types for driving independent loads, and one high-pass (HP)
current output, flowing through one of the working capacitors. Other
implementations of various types of transfer functions are proposed by means
of commonly used methods of input/output current summing. Their critical
analysis is accomplished from the point of view of tracking errors and dynamic
range optimization. Results of the PSpice simulation, which utilizes the CDTA
model on the level of CMOS transistor structure, are enclosed.
Keywords: CDTA, PSpice, Current-mode filters
Title of the Paper: Realisation of
Single-Resistance-Controlled Sinusoidal Oscillator: A New Application of the
CDTA
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Authors:
Dinesh Prasad, D. R. Bhaskar, A. K. Singh
Abstract: Among various modern active building blocks, the recently introduced
’current differencing transconductance amplifier’ (CDTA) is emerging as a very
flexible and versatile building block for analog circuit design and has been
used earlier for realizing a variety of functions. In this paper, a new
application of the CDTA in realising a Single Resistance Controlled Sinusoidal
Oscillator has been introduced. The proposed circuit employs only a single
CDTA alongwith a bare minimum of only four passive components and yet offers
the advantages of (i) independent control of condition of oscillation and
frequency of oscillation and (ii) low active and passive sensitivities. The
workability of the proposed configuration has been demonstrated by
experimental results.
Keywords: Current Differencing Transconductance Amplifier, Sinusoidal
oscillator, Current-mode circuits
Title of the Paper: CDTA Based
Transimpedance Type First-Order All-Pass Filter
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Authors:
N. A. Shah, Munazah Quadri, S. Z. Iqbal
Abstract: This paper presents a transimpedance type first-order all-pass
filter using a single current differencing transconductance amplifier (CDTA)
and one each of capacitor and resistor which is the bare minimum requirement
for such type of filter. The circuit is free from the realizibility condition
and permits electronic and independent adjustment of gain. The simulation
results are also included.
Keywords: All-pass filter, Current differencing transconductance amplifier,
Analog signal processing
Title of the Paper: Synthesis of
Switched Current Memory Cells Using the Nullor Approach and Application to the
Design of High Performance SI Sigma Delta Modulators
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Authors:
Mourad Fakhfakh, Siwar Masmoudi, Esteban Tlelo-Cuautle, Mourad Loulou
Abstract: This work presents the design of switched current sigma delta
modulators. The nullor approach is adopted to synthesize voltage followers
used to design translinear-loop-based switched current memory cells. Besides,
it is proposed an approach for computing optimal biases and sizing of
transistors forming the modulator. This heuristic allowed us sampling a second
order modulator up to 80MHz, ensuring more than 60dB of SNR.
Keywords: Switched current technique, Voltage follower, Nullor, Heuristic,
Sigma Delta Modulator
Title of the Paper: Optimizing LC VCO
Performances Through a Heuristic
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Authors:
Ibtihel Krout, Hassene Mnif, Mourad Fakhfakh, Mourad Loulou
Abstract: We propose a heuristic for the optimal sizing of LC VCO’s. The
heuristic is an algorithm driven methodology that allows us determining
optimal sizes of inductors and channel widths that minimizes the VCO’s phase
noise while satisfying fixed constraints (maximum consumed power, occupied
area…). The proposed optimization methodology was applied to size a
cross-coupled differential voltage controlled oscillator. This latter,
designed using AMS 0.35 μm technology, achieves -124.9 dBc/Hz at 1MHz offset
from a 2.6 GHz carrier frequency with 8.2mW consumption power and -118.7 dBc/Hz
at 1MHz offset from a 5.4 GHz carrier frequency with 8.0mW consumption power.
Keywords: LC-VCO, Heuristic, Phase noise
Title of the Paper: Symbolic Analysis of
Linear Circuits with Modern Active Elements
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Authors:
Zdenek Kolka, Dalibor Biolek, Viera Biolkova
Abstract: The paper deals with the symbolic analysis of linear circuits with
modern active elements using the SNAP program. The simulator can perform both
classical and approximate analyses. All device models are stored in a text
library, which can be easily extended. Device parameters can be defined as
simple symbols or as formulae in the netlist. This allows the simulation of
electronic circuits both with basic elements and with complex behavioral
models.
Keywords: Symbolic Analysis, Symbolic Approximation, Linear Circuits, Active
Elements
Issue
7, Volume 5,
July 2008
Title of the Paper: Hierarchical
Clustering based Automatic Refactorings Detection
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Authors:
Istvan Gergely Czibula, Gabriela (Serban) Czibula
Abstract: The structure of software systems is subject of many changes during
the systems lifecycle. A continuous improvement of the software systems
structure can be made using refactoring, that assures a clean and easy to
maintain software structure. In this paper we are focusing on the problem of
restructuring object oriented software systems using hierarchical clustering.
We propose two hierachical clustering based algorithms which takes an existing
software and reassembles it using clustering, in order to obtain a better
design, suggesting the needed refactorings. We evaluate the proposed
algorithms using the open source case study JHotDraw and a real software
system, providing a comparison with previous approaches.
Keywords: Software engineering, system design, object-oriented systems,
refactoring, clustering, algorithm
Title of the Paper: Technological Status
and Market Trends of Photovoltaic Cell Industry
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Authors:
Irfan Guney, Nevzat Onat
Abstract: In this study, technological developments and market tendencies in
photovoltaic cell (PV) industry are investigated. The increasing energy demand
and decrease in conventional energy resources orientates researches to be in
tendency to continuously increase the output of alternative energy resources.
Today, crystal silicon cells significantly dominate tendencies in PV Cell
market with their converting outputs exceeding 20% in small areas. However, a
PV panel with silicon crystal is very expensive. To increase output efficiency
by decreasing costs of PV cells and modules, nanotechnology approaches are
very important. Nanomaterials that used in PV cell production, absorb sunlight
better, increase the energy transformation and cheaper than other materials
but require special fabrication fixtures. PV cell market is dominated by Japan
and Germany. Installation tendencies are become dense on grid-connected
systems. Although the costs of PV module per watt generally follow a
horizontal route, system installation costs decrease regularly.
Keywords: Silicon PV Cells, Nanotechnology, Thin Film, Dye-Sensitized,
Efficiency, Installation Cost
Title of the Paper: A High Performance
AC Permanent Magnet Contactor
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Authors:
Chieh-Tsung Chi
Abstract: This paper describes a simple colenoid actuator mechanism and its
electronic control circuit (ECU) that allows new ac permanent magnet (PM)
contactor to perform the making and breaking course without critical
disadvantages imposed by the previous ac electromagnetic (EM) contactor, such
that consumes much energy to hold armature, produces noise at lower voltage
and their coils are easy to be burnt due to continual energization, and incurs
abnormal dropouts owing to voltage sag. First, the control circuit of colenoid
actuator is derived and then experimental tests are carried out to verify the
effectiveness of the control circuit. Then, a theoretical model is built and
the dynamic characteristic of the proposed colenoid actuator is identified.
Finally, the fast transition and energy saving of the proposed ac PM contactor
are demonstrated by experimental and simulation approaches.
Keywords: Electronic control unit (ECU), colenoid actuator, ac PM contactor,
ac EM contactor, energy saving, voltage sag
Title of the Paper: Towards the Control
of a Permanent Magnet Contactor Based on Charging and Recharging Techniques
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Authors:
Chieh-Tsung Chi
Abstract: This paper presents the design and analysis of a newly actuator with
hardware based electronic control unit (ECU) for the control of energy
dissipation in ac permanent magnet (PM) contactor. By using charging and
recharging techniques, the making and breaking operations of contactor are
controlled by ECU. In typical application where the gate driving signals of
the closing and the opening power MOSFETs are limited to be produced during
the closing and opening processes. In theory, no input electrical energy will
be dissipated in the ac PM contactor during holding stage. Crucial to the
design of the ECU is that has several outstanding benefits, such as
simplicity, low cost, no noise pollution, energy saving and no voltage-sags
affections. This paper describes the designing considerations for such a newly
proposed ECU for use in a 220 V contactor control. Tests on experimental and
simulation results illustrate the characteristic behaviors of the ac PM during
making and breaking courses, and comparison evaluations of the energy-saving
performance over a time interval between conventional ac electromagnetic (EM)
contactor and proposed ac PM contactor.
Keywords: Electronic control unit (ECU), ac permanent magnet (PM) contactor,
energy saving, no noise pollution, ac electromagnetic (EM) contactor
Issue
8, Volume 5,
August 2008
Title of the Paper:
A High-Frequency Voltage-Follower with Global Feedback
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Authors:
N. Charalampidis, M. Spasos, N. Mallios, K. Hayatleh, B. L. Hart, J. F. Lidgey
Abstract: A popular form for a voltage-follower (VF) with global feedback is a
voltage operational amplifier (Op-Amp) with 100% negative feedback.
Nevertheless, with currently available Op-Amps it is unable to meet high
frequency specifications. This paper presents a high frequency
voltage-follower based on an overall feedback technique. Despite the global
feedback loop, the design presented small-signal bandwidth higher than 3GHz
and gain flatness to within 0.1dB up to 170MHz. Due to this feedback loop, the
circuits exhibits very high input and very low output impedance. In addition,
the output voltage swing achieved is some ±3V, with an input offset current of
around 130nA and an offset voltage in the range of 200uV. The proposed circuit
is very stable, due to the stability technique used, maintaining low
distortion. The total harmonic distortion (THD) of the circuit is better than
-65dB and the intermodulation distortion (IMD) is some -70dB, for capacitive
loads up to 10pF. The analysis of the novel circuit has been carried out for
operating temperatures from -20oC to +100oC, using
Analog Devices’ extra fast complementary transistors. The power dissipation is
some 52mW on a ±5V power supply, although it can be reduced to ±3.3V, without
affecting significantly the performance, depending on the application.
Keywords: Voltage-follower, buffer, low distortion, high frequency, global
feedback
Title of the Paper: Synthesis of
Multi-Level Dual Reed-Muller Forms
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Authors:
Khalid Faraj
Abstract: This paper introduces the fundamental theory, algorithms, and
terminology regarding synthesis of multi-level Dual Reed-Muller expressions.
The increasing interest in using Dual Reed-Muller expressions as a way of
representing and manipulating switching functions, and as a mean of designing
circuits based on OR/XNOR gates has led to this research. Up to present there
are only two-level Dual Reed-Muller minimization algorithms in use, although
the need for multi-level minimization algorithms has been recognized. A new
theory and algorithms for multi-level Dual Reed-Muller minimization have been
developed. It introduces a Dual Reed-Muller factored form and uses algebraic
algorithms for factorization decomposition, re-substitution, and extraction of
common cubes and sub-expressions.
Keywords: Multi-level Dual Reed-Muller forms, factorization, decomposition
Title of the Paper: Variable Lateral
Silicon Controlled Rectifier as an ESD Protection
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Authors:
Petr Betak, Vladislav Musil
Abstract: The Variable lateral Silicon Controlled Rectifier (VLSCR) is a SCR
based structure with the possibility to tune I-V snapback characteristics.
This effect is important for an ESD (electrostatic discharge) protection
design. The ESD protection structures act as a protection of integrated
circuits against parasitic electrostatic discharge. Among often used
structures belong structures having snapback type of I-V characteristic.
Typical is a gate-grounded NMOS transistor [3] or a SCR [3]. This text is
dealing with the VLSCR structure which enables I-V snapback characteristics
tuning according to the application demand. Simulated technology was 0.5μm
CMOS very high voltage (VHV Integrated Circuits). Measurement was done in 1.5
μm BiCMOS process.
Keywords: ESD, SCR, LVTSCR, VLSCR
Title of the Paper: Full-Scale Nonlinear
Analysis of LHL Ga As IMPATT Amplifiers
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Authors:
Said H. Ibrahim, Hosny A. Al-Motaafy
Abstract: The analysis of LHL Ga As IMPATT Diode structure has been developed
on the basis of IMPATT nonlinear model. The paper presents a detailed analysis
of the effect of peak value of the microwave signal and the operating
conditions on the performance of GaAs IMPATT amplifiers. It is indicated that
the variation of peak RF voltages gives rise to three modes of operation
(conventional mode and two high-efficiency modes) . During the high-efficiency
modes, the induced current has one or two additional peaks at the proper phase
angles in the RF cycle due to the bunching and acceleration of the
avalanche-generated packet of electrons. The diode conductance and the
generated RF power increase sharply during the high-efficiency operation.
Important conclusions concerning the effects of the dc bias current and
operating frequency on the performance of this device are drawn. The results
presented here are obtained using a full-scale computer simulation program
that takes fully into account all the physical effects pertinent to the IMPATT
diode operation .They will help optimize the Ga As IMPATT structure and its
operating conditions.
Keywords: Computational Microstrip Circuit Design, Microwave Circuits,
Computer Aided Design
Title of the Paper: Performance
Optimization of OSAJ P-Type Ga As IMPATT Diodes
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Authors:
El-Sayed A. El-Badawy, Said H. Ibrahim
Abstract: The study of OSAJ p-type Ga As IMPATT diode is important in order to
get better insight into the operation of this type, which is not sufficiently
studied. Hence it will be possible to design and optimize the structure of
double-drift Ga As IMPATT and the circuit where this IMPATT is embedded. This
paper presents the results of detailed study for performance optimization of
OSAJ p-Type Ga As IMPATT Diode structures. This study used the full-scale
computer simulation program performed by the authors taking into consideration
the nonlinearities and all physical effects pertinent to the IMPATT operation.
Some important conclusions concerning the effect of the peak value of the
microwave signal, the effects of the operating dc-bias current and the
operating frequency on the IMPATT operation and performance are drawn. The
complete simulation curves for the operation of OSAJ p-type IMPATT diodes are
introduced.
Keywords: Microwave Circuit Design, Microwave Devices, Computer Aided Design
Issue
9, Volume 5,
September 2008
Title of the Paper: Wavefunction-Engineering
of the Optoelectronic Yield for Intersubband THz-Laser Nanodevices
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Authors:
E. A. Anagnostakis
Abstract: A novel THz-luminescence LASER nanoheterostructure of the
intersubband, longer-wavelength limit, mid-infrared functionality type is
designed on the basis of optically pumped dual resonant tunnelling of
conductivity electrons within an appropriately energetically determined scheme
of five subbands hosted by two communicating asymmetric approximately
rectangular quantum wells (QWs). The upper LASER action level employed is the
second excited subband of the nanostructure back, wider QW and is being
provided with electrons via resonant tunnelling from the first excited subband
of the nanostructure front QW being populated through remotely ignited optical
pumping out of the local fundamental subband. As the lower LASER action level,
on the other hand, functions the first excited back QW subband, directly
delivering the received electrons to the local fundamental subband – via a
fast vertical longitudinal optical phonon scattering-, wherefrom they are
being recycled back to the nanostructure front QW fundamental subband by
virtue of a second – reverse sense – resonant tunnelling – mediated normal
charge transport mechanism. LASER action level population inversion and
intersubbad transition (ISBT) effective dipole lengths are critically
monitored in connexion to the pertinent ISBT oscillator strengths and device
stimulated optical gain achievable.
Keywords: Nanodevice, Optoelectronics, THz-LASER, Wavefunction-Engineering,
Intersubband Luminescence
Title of the Paper: On Plus-Type Nullor
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Authors:
Chun-Li Hou, Jiun-Wei Horng, Chun-Ming Chang, Chao-Yu Hung, Wei-Ching Chang
Abstract: It is well-known that a nullor of the negative-type is a two-port
with the null transmission matrix. But there is no obviously mathematical
definition for a plus-type nullor. The authors proposed a matrix definition
for a nullor of the plus-type. Besides, this paper derives out the adjoint
component of a plus-type nullor. A voltage-mode amplifier, an oscillator and a
current-mode biquadratic filter that using plus-type nullors are transformed
to their adjoint circuits as examples to demonstrate the usefulness of the new
component. Simulation results are given to confirm the theoretical analysis.
Keywords: Nullor, Adjoint network, Circuit theory, Current-mode, Active
circuit
Issue
10, Volume 5,
October 2008
Title of the Paper: Methodical Self
Checking and Test Infrastructure Design for Fault Tolerance in Digital
Circuits
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Authors:
Y. Rajasree, Y. Vishnu Priya, N. R. Alamelu
Abstract: During the process of development of any system, system reliability
is of utmost importance .Specially when designing a processor, it is desired
that a processor function correctly even in the presence of faults .This
concept is commonly referred to as fault tolerance. The fault tolerant
microprocessor systems used in safety critical applications need to be
thoroughly validated during the design stages. As feature size reduces in
future, there is an increased probability of transient and intermittent
faults. Transient faults can only detected by online detection or concurrent
checking and not by testing . Because of continuously shrinking dimensions and
voltage levels in near future transient faults will be a major source of
errors. Therefore concurrent checking is becoming all the more important and
necessary. Now these systems on chip integrated circuits contain both digital
and analog cores. Test cost for such mixed signal SOC is much higher than the
digital SOC that allows the analog and digital cores to be tested. The analog
cores are wrapped such that the test can performed using a digital test access
mechanism .In our method , an analog test infrastructure is used which
consists of test wrappers and test access mechanism. Test wrappers isolate
various modules from their surrounding circuitry during test .So the focus is
on optimisation of a unified test access architecture that is used for digital
and analogue cores. We wrap each analog core by a pair of digital to analog
converter and analog to digital converter .They convert analog core to virtual
digital core which allow the use of digital testers to test the analog cores.
This reduces the need for expensive mixed signal tester so that there is a
reduction in the overall cost. The work demonstrates an implementation of a
design methodology for embedding fault tolerant capabilities into high level
digital system design.
Keywords: Fault, Multiplier, Adder, wrapper, carry, ADC , Synthesis, Sampling
Title of the Paper: Research on k-Fault
Diagnosis and Testability in Analog Circuit
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Authors:
Wei Liao, Jingao Liu
Abstract: Fault diagnosis is very important for development and maintenance of
safe and reliable electronic circuits and systems. Many k-fault diagnosis
methods were put forward such as branch method, node method, loop method, mesh
method, cut set method. But the tolerance effect as well as non-linear
problems exist and are difficult to deal with. A fault diagnosis method for
analog circuit is proposed in this paper, including the mathematical model and
two improved algorithms about K-node method and K-branch method. The potential
of the algorithms is demonstrated by an order active circuit example and the
workload of the verification can be reduced. For the testability problems of
analog circuit, testability analysis and testability design are researched
under prescriptive condition. A testable topological condition which has
nothing to do with the circuit parameters is put forward, and the testability
analysis and testability design are carried out by a variety of convenient and
flexible ways. The method is extended to the testability problems of analog
circuit, and result shows that the testability problems of analog circuit can
be resolved effectively without any other complex numerical computation.
Keywords: K-fault diagnosis, fault diagnosis, fault verification, analog
circuit, K-node method, K-branch method, testability
Title of the Paper: Application Specific
Scalable Architectures for Advanced Encryption Standard (AES) Algorithm
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Authors:
S. S. Naqvi, S. R. Naqvi, S. A. Khan, S. A. Malik
Abstract: The work presented proposes two diverse FPGA based architectures
with high-speed and low area constraints for suitable implementation of
Advanced Encryption Standard (AES). The main focus of this paper is to compare
different design architectures existing in literature with the proposed ones,
based on application specific constraints. The high speed design presented
here proposes a good engineering solution to high speed applications where
area constraint can not be totally neglected. The high speed design manages to
achieve a reasonable 6 Gbps throughput despite of the fact that it only covers
mere 5800 slices in area .Low area architecture achieves a decent throughput
of 1.98 Mbps with low slices count of 297. Some common applications of high
speed design include broadband switches and firewall, whereas the low area
design mainly focuses on compact applications like PDAs and cell phone in
which area and power constraints are critical. Both the designs are
implemented and tested using a Xilinx Spartan-III (XC3S2000) target device.
Keywords: Advanced Encryption Standard (AES), Subpipelined, High Speed, Low
Area, Unrolled architecture, Cryptography, Throughput, FPGA, and Data
Encryption Standard (DES).
Issue
11, Volume 5,
November 2008
Title of the Paper: MQW Design Parameter
Variation in a 1.5 μm Wavelength InP-based LW-VCSEL
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Authors:
K. Kumarajah, P. Menon, M. Ismail, B. Y. Yeop, S. Shaari
Abstract: Long-wavelength vertical-cavity surface-emitting lasers (LW-VCSEL)
have profound advantages compared to traditional edge-emitting lasers and its
commercialization is gaining momentum as the local and access network in
optical communication system expands. In this paper, we present the design
parameter variations of multi quantum wells (MQW) in the active region of an
InP-based long-wavelength vertical-cavity surface emitting laser (LW-VCSEL)
utilizing an air-post design. The MQW and barrier thickness were varied and
their effect on the device threshold current, optical power, gain, lattice
temperature, peak wavelength and reflectivity were analysed and presented.
Quantum well thickness of 5.5 nm and barrier thickness of 8 nm gives the
optimum threshold current of 0.579 mA, optical power output of 4.2 mW, modal
gain of 27 cm-1, lattice temperature of 310.6 K and peak wavelength of 1.562
μm.
Keywords: VCSEL, MQW,
InGaAsP, threshold current, gain, air-post
Title of the Paper: Modeling of an
Optical Diaphragm for Human Pulse Pressure Detection
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Authors:
K. Hasikin, N. Soin, F. Ibrahim
Abstract: This paper presents the modeling of an optical diaphragm behavior
for human pulse pressure detection. In this study, the comparison between the
performance of the polyimide and silicon nitride diaphragm has been presented.
The effects of diaphragm radius and diaphragm thickness on static and
frequency response are also investigated. The findings show that the polyimide
diaphragm is more sensitive than the silicon nitride diaphragm. In addition,
deflection of both diaphragms has linear relationship with the applied
pressure The diaphragm radius has more effect on the deflection, sensitivity
and resonance frequency as compared to the diaphragm thickness. It can be
concluded that the polyimide diaphragm achieves the optimum performance in
terms of the deflection, sensitivity, and resonance frequency for human pulse
pressure detection. Thus, the polyimide diaphragm has been chosen as the best
model in designing an optical micro-diaphragm.
Keywords: Optical MEMS,
Deflection, Resonance Frequency, Pressure Sensitivity, Pulse Pressure, Silicon
nitride, Polyimide, Biosensor
Issue
12, Volume 5,
December 2008
Title of the Paper: Study on a System
for LED's Photometric and Colorimetric Measurement based on a Multi-Channel
Spectrometer
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Authors:
Xiaoli Zhou, Muqing Liu, Yong Qian, Hui Wang, Shaolong Zhu
Abstract: Light Emitting Diode (LED) is quite different from traditional light
sources in many aspects. In this paper the practical aspects of LED’s
measurement and problems are discussed. An integrating sphere system is
designed and implemented for LED measurement based on a multi-channel
spectrometer. The principle and procedure of the measurement are presented,
and then the measurement errors are analyzed. The spectrometer uses a
Self-scanning Photodiode (SPD) Array device as the detector which has 256
pixels and ultra-high sensitivity. The system can fulfil fast and accurate
measurement for LED’s photometric and colorimetric quantities such as total
luminous flux, Color Temperature, Color Rending Index (CRI) and color
coordinate. This method can avoid the measurement errors by self-absorption
effect and mismatch of V (λ).
Keywords: Light
Emitting Diode (LED), spectrometer, photometric, colorimetric, SPD,
integrating sphere
Title of the Paper: Evolution from 3D to
4D Radar
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Authors:
Maria Gutierrez, Gerardo Aranguren, Miguel Rodriguez, Javier Bilbao, Javier
Gomez
Abstract: The increase in air traffic has the immediate consequence of
creating new techniques for air traffic control, as well as new procurement
data procedures and data reporting. For these purposes, secondary radars have
been developed under the standard ADS-B that should be implemented in coming
years on a mandatory basis. In this article, an application of ADS-B radars,
capable of introducing the air traffic in real time using a simple form of 4D
representation and a free graphical interface. This application, consisting of
a network of computers arranged in three layers (Layer of ADS-B Data
Acquisition, Business Logic Layer and Presentation Layer), offers numerous
advantages to flying clubs, academies of pilots, control towers, air traffic
controllers, aircrafts (IN ADS-B), airlines (green trajectories), airport
service vehicles, and so on
Keywords: ATM, ADS-B, Virtual Radar, Google Earth, 4D Visualization, GIS
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