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Virtual Wireless and Mobile Communication Laboratory

Abstract and Figures

Creating a virtual laboratory for distance learning courses has become recently so important recently for engineering education. In this paper, we provide a full description for a remote access technique used in a wireless and mobile communication laboratory. Hence, the student will be able to perform experiments online and controlling and watching the devices by accessing a camera already built in the laboratory. Signal generator, spectrum analyzer and field-fox devices are used in the virtual laboratory.
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Virtual Wireless and Mobile Communication Laboratory
Ahmad Nassar
1
, Motaz Mohammed
2
, Ali Elrashidi
3
and Khaled Elleithy
4
1 Department of Computer Engineering, University of Bridgeport, CT 06604, USA (anassar@bridgeport.edu)
2 Department of Computer Engineering, University of Bridgeport, CT 06604, USA (motazm@bridgeport.edu)
3 Department of Computer Engineering, University of Bridgeport, CT 06604, USA (aelrashi@bridgeport.edu)
4 Department of Computer Engineering, University of Bridgeport, CT 06604, USA (elleithy@bridgeport.edu)
Abstract Creating a virtual laboratory for distance learning courses has become recently so important recently for
engineering education. In this paper, we provide a full description for a remote access technique used in a wireless
and mobile communication laboratory. Hence, the student will be able to perform experiments online and controlling
and watching the devices by accessing a camera already built in the laboratory. Signal generator, spectrum analyzer
and field-fox devices are used in the virtual laboratory.
Keywords Virtual laboratory, remote access, distances learning, signal generator, spectrum analyzer, field-fox
device.
1. Introduction
Studying a course via the internet means that a student can
interact with their teacher via email and video conferences.
This educational method requires a high degree of maturity
on the student behalf, therefore it is more suitable for grad-
uate students and senior undergraduates who are taking
courses that require practical laboratory practices [1].
With the beginning of the internet for more than two dec-
ades ago, distance education has been introduced and ex-
panded through universities and schools. One of the most
important factors of distance education was the develop-
ment of “distance experimentation”. This kind of education
focuses mainly on practical aspects of instructional systems,
to give students theory and practices and also to help teach-
ers and professors who are not always physically on site.
There are a lot of difficulties in this area and there has not
been so much work done in this kind of educational field
until lately.
Remote access experimenting has become so important
recently for engineering education because it made it easier
to provide more lab hours and also make efficient use of
equipments and providing convenience for offsite
students [2].
Since 1994, Engineers and others have established the pos-
sibility of making distance experimentation easy and acces-
sible by student for their practical experiments and using
the internet as a way to learn. One of the earliest experi-
ments and approaches to distance experimenting was robot
control and some circuit fundamental experiments [3].
As universities expand distance education programs, they
offer educational opportunities in different market sec-
tors than they usually operate. Universities may use this
new technology to attract students in nontraditional
markets in which could result in competition or coopera-
tion between universities. Universities may also share
access to one internet based access of this new technolo-
gy.
For distance experiment, it is really important to provide
very high quality lab experience to the offsite students.
Early remote access lab implementations were proofs of
the practicability of this new Technology which has ab-
sorbed much of the cost of providing lab services to a
limited set of students.
Many public universities have faced budget cuts over the
past few years, the support needed for computing sys-
tems and labs was usually provided by graduate teaching
assistants, who change from one semester to another.
decisions must be made on how this new technology
should be delivered according to who should provide the
laboratory services , what kind of support , what are the
available lab hours needed, and finally what kind of in-
frastructure is required for distance experimenting [4].
2. Related Work
One of the newest and increasingly popular technologies is
remote lab access. With the world wide spread of the Inter-
net and multiple applications that come with it, remote ac-
cess technology has become a high demand technology [5].
An electronic remote access FPGA laboratory was devel-
Laboratory Server
Internet
Student
Lab Server
Student
Lab Server
oped by Hashemian and Riddley [5]. This system was in-
tended for the use of the FPGA and Xilinx's Spartan-3E
Starter Kit that are used in digital logic design laboratory.
The remote desktop application provided by windows XP is
used to connect a user with the FPGA board, LabView, and
hardware such as an integrated webcam, GPIO and data
acquisition. GPIO and the integrated webcam then connect
to the switches, LEDs, push buttons and the rest of the
hardware on the FPGA board itself. A benefit of using this
methodology is the inexpensive setup cost that comes with
the FPGA Spartan-3E Starter kit. However, using windows
XP remote desktop kit slows down the system.
NetLab design started in the University of South Australia
and was developed in order to overcome the most common
problems regarding remote access laboratory. The architec-
ture of NetLab is similar to previous work, but in addition it
includes a selection of materials and equipment incorpo-
rated in the design and it allows collaboration between mul-
tiple users. The end result of the Netlab research was that
standard working labs outperform remote access labs.
To evaluate the proficiency of conventional labs simulated
labs, and remote log in labs, Corter et.al. [6] proposed a
model to compare the results of each [7]. The main focus of
the experiments was the motion and activity of apparatus
such as cameras, microphones, connection and gears. Six
experiments were executed; three of them were hands-on in
person and the other three were remote lab access. The re-
sults that were closely looked at by the conductors were
preferences and overall satisfaction.
Learning ability and their style of thinking were the main
characteristics related to students preferred remote access
laboratories [7]. The final results showed that the least pref-
erable criteria by students included team work, pre lab ex-
periments, final reports and not surprisingly the attendance
of the lab. The degree of how much a student learned from
the experiments was tested by professors on the midterms
and final exams.
Remote laboratory access was also used for an optical cir-
cuit class [8]. The purpose was to educate the students about
the basics and concepts before moving on to pre laboratory
work [9]. Pre-laboratories had on-line material that consists
of an introduction video, results, and the step by step labor-
atory procedures. The learning outcome was measured and
the teaching methods were assessed. Students were required
to connect to a LabView web Server using a specific client.
Afterwards, they were required to perform three experi-
ments.
The characterization of optical source circuits, the attenua-
tion of optical fiber links and connectors, and practical
skills obtained by students from performing remote labs.
The success was measured based upon how successful each
student was in conducting these three experiments. After-
wards, a student survey was taken to gauge their opinion.
The ILab technology was first developed at the Massachu-
setts Institute of Technology (MIT) [10]. A remote access
biology laboratory was prepared by Elawady et.al. using the
ILab. The benefits of performing a general biology lab re-
motely according to Elawady et.al. were that resources and
costs are shared, which leads to a more efficient and pro-
ductive work environment. The work by Elawady et.al.
inspired other researches to start looking into remote access
laboratory in their fields and acknowledging some of the
benefits that come along with it.
One field that is being looked into is FPGA because the
boards themselves can be manipulated and are flexible.
There is not that much work out there that involves remote
accessing the FPGA board, however, more research is being
carried out and the interest is growing [11].
3. Proposed Laboratory Overview
In Figure 1, the overall proposed laboratory is illustrated.
The student will be able to access the laboratory server via
Internet and by using username and password assigned by a
laboratory monitor student can access the laboratory devic-
es. By using an integrated camera in the lab, the student will
be able to check any experiment connections or electronic
circuit connections.
Signal generator and spectrum analyzer are used to generate
and analyze signals for most of the experiment in the de-
signed laboratory. Field-fox device is used as either network
analyzer mode or signal generator mode. Field-fox is a very
efficient device in most of experiments in the laboratory.
A camera is connected to a personal computer very close to
the devices and mainly controlled by a laboratory monitor
person. A student is able to access the camera via internet
connection to watch the devices setup in the laboratory.
A lab monitor will be responsible for giving a username and
password to each student registered in course, do the setup
for experiment each week and set a time slot for each stu-
dent, so the student can access the devices in his/her own
time slot during the week.
Figure 1. Overall system overview for accessing the virtual laboratory
Internet
Any experiment can be accessed by only one student at a
time, and the student can chat immediately with the labora-
tory monitor if the student has any questions or concerns.
4. Remote Access to the X-Series Signal
Analyzer and the MXG Signal Generator
There are two instruments that the virtual laboratory can
use remotely logged into; the X-Series signal analyzer
and the MXG signal generator. For the X-series signal
analyzer, the remote login in can be achieved via the lo-
cal area network (LAN) or using an embedded web serv-
er. On the other hand, for the MXG generator, remote
login can only take place through a web-enabled page
because it is not running on any operating system.
1. X-Series signal Analyzer
a) LAN configuration
The initial step is to set up the instrument and prepare it
to remotely connect to a computer. An administrator lev-
el access to the instrument is required. The following
steps are executed:
1. First, go to the control panel on the instrument
and double click on system.
2. Next, click on the remote tab and ignore the
warning message that pops up.
3. Then check the box to allow users to remotely
use this computer and click the select remote
users and then add.
4. Follow the on-screen instructions and now the
Signal analyzer can be accessed.
Now that the instrument is set up, the next step is to set
up the remote host computer. First, the remote desktop
connectivity software is needed. If windows XP or any
later operating system versions are being used, it auto-
matically comes installed with it. If using an earlier
windows version, the software must be installed from a
CD. The next step is to get the instrument’s name by
pressing system, show, system on the front panel and the
name will appear.
To start the remote desktop session, from the remote
computer, go to start, all programs, accessories, commu-
nication, remote desktop connection and then enter the
name of the instrument you have obtained and click
connect. Enter the login and password and click ok
which will bring up the remote desktop connection
screen. Ensure that the login name, password, and com-
puter name are all correct and then under local resources,
check the disk drives and printer boxes to enable transfer
between the instrument and the computer, and click con-
nect. This will make the remote desktop connection and
as Figure 2 display.
Figure 2. spectrum analyzer results
If you navigate to utility, virtual front panel, a panel
identical to the instrument’s front panel will appear as
shown in Figures 3 and 4.
a) Internet connection
Using an embedded Web server is valuable when you
cannot log onto the instrument’s account. You can wire-
lessly connect to the instrument without needing to log
the current user off. Also, this function only works with
Internet explorer. The first step is to enter the URL con-
sisting of the hostname or IP address, which will take the
user to the welcome page. On the welcome page, there
are tabs that enable the user to change any configuration
on information about the instrument, and it is easy to
change or modify them. Next, click control and enter the
password (which is “Agilent” by default). This will bring
up instruments control web page, and then by clicking
display front panel keys, a virtual keyboard will appear
identical to the figures from the desktop remote login
method.
Figure 3. first spectrum analyzer virtual panel
Figure 4. second spectrum analyzer virtual panel
2. MXG Signal Generator
The only way to remotely access the MXG signal gener-
ator is through a web-enabled client. To do so, enter the
URL starting with a- then follow by instrument’s model
name and the last five digits of the instruments serial
number. This will take you to the homepage. By clicking
signal generator web control from the menu, the virtual
front panel of the MXG generator will appear. If asked
for a password, by default it is set to “Agilent”. The
screen shot below shows the virtual front panel, Figure 5.
Now that the virtual front panel has been accessed, it is
advised to adjust the brightness of it and turn the screen
saver off. Also, the panel can be easily configured to
match the specifications of the used operating system.
Generating a signal can be easily done by manipulating
the frequency on the panel as desired.
Figure 5. signal generator panel
3. Field-Fox Analyzer
The Field fox analyzer is a portable instrument which is
used on the field to analyze signals and networks. The
field Fox analyzer instrument has a LAN port but how-
ever it wasn’t designed for to remotely login on the in-
strument because of its portability.
However we have been able to figure out how to remote
access to the device using specific software (remote dis-
play control for windows CE) although the LAN port on
the device was designed for and used for sending and
receiving data files only.
The Remote display control for windows CE is simple
software that is basically used for remote accessing mo-
bile devices and since the field fox analyzer is in the
same category we were able to remote access the device
using that software [12].
Details on how to remotely access the Field Fox analyzer
is shown next. First we need to set up the instrument and
connect to the Internet via an LAN cable. After that we
start setting up the network for the device by assigning it
an IP address which will be used to login on the device
we do that by going to “system preferences” and then we
choose “LAN”. All network settings will show up so we
scroll down to “apply setting” and then we choose
“power up”, the device will present the LAN settings and
give the device an IP address.
Once the instrument is set and ready, we use any com-
puter and launch the “remote display control “application
as in Figure 6.
Figure 6. remote display control for windows CE
Next we click on file” and then click on connect”. A
pop window will show up asking to enter the IP address
of the mobile device we wish to connect to as in Figure
7.
Figure 7. accessing the device via its IP address
Once you click “OK”, the application will have full re-
mote access to the device as in Figure 8.
As for controlling the device the mouse of the computer
should be able to control the device and also for some
special keys such as numbers they can be used from the
regular keyboard of the Computer.
Figure 8. field-fox display
5. Accessing an Experiment
A student will be able to access the devices after listening to
a short demo, posted in the virtual laboratory website, de-
scribing the accessing procedures. The laboratory monitor is
responsible for electrical connections for the experiments in
the laboratory.
Measuring the performance of a microstrip
antenna
In this experiment, the student is required to measure the
performance of a printed microstrip antenna. Those param-
eters are voltage standing wave ratio, return loss and input
impedance for a flat microstrip printed antenna and the
measurements should be done in two parts as shown bellow.
Figure 9, appears when the student access the camera. In
Figure 9, a flat microstrip antenna connected to the signal
generator and the antenna under test is connected to the
spectrum analyzer. In the first part of the experiment, stu-
dent need to set the frequency of the signal generator to be
2.5 GHz from the signal generator panel and set the ampli-
tude to be -10 dBm.
The measurements will be shown in the spectrum analyzer
screen. It can be controlled using analyzer virtual panel, as
introduced in the previous section. The image of the spec-
trum analyzer is shown in Figure 10. A peak at 2.5 GHz is
obtained on the spectrum analyzer panel, and the peak value
can be measured by using the marker from the control panel
of the analyzer.
In the second part, the student is asked to measure some
parameters to get the performance of the antenna. Those
parameters are voltage standing wave ratio, return loss and
input impedance of the antenna. Figure 11 shows the
field-fox device that measures the return loss of the con-
nected antenna. The student is able to change the starting
and ending frequencies to clearly show the performance
parameter of the antenna.
Voltage standing wave ratio and input impedance of the
designed antenna can also measured using a field-fox de-
vice.
Students can save the output data in a Matlab format in their
personal computer and analyze the data using Matlab pro-
gram. The output data is shown in Figure 12 using Matlab
program.
Figure 9. performance measurement of a microstrip printed antenna
Figure 10. screen shut of the spectrum analyzer
Figure 11. voltage standing wave ratio for the designed antenna shown in
field-fox device
Figure 12. return loss as shown in Matlab program
6. Conclusion
In this paper, we introduce the mobile and wireless virtu-
al laboratory that is designed to be one of the distance
learning courses. A full description of the remote access
technique used for the wireless and mobile communica-
tion laboratory using a fixed camera in the laboratory is
introduced. Accessing the signal generator, spectrum
analyzer and field-fox devices then controlling these de-
vices using remote access technique are introduced.
An implementation of a real experiment in the wireless
and mobile communication laboratory for a microstrip
antenna is given in this paper. Return loss, voltage
standing wave ratio and input impedance for a microstrip
printed antenna are measured and saved in the personal
computer and processed in Matlab software program.
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[4] shor, “Remote-Access Engineering Educational Laboratories,
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[6] http://vipmeister.com/dl/netlab/netlab.html
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Annual, 2003.
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[10] Elawady, Yasser, and Tolba “A General Framework For
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[12]http://na.tm.agilent.com/fieldfox/download_files/cerhost60.zip
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A Techinique to Remote Access a Laboratory to Design and Test
  • Reza
  • Fpga E-Lab
Reza, " FPGA E-Lab, A Techinique to Remote Access a Laboratory to Design and Test, " IEEE International Conference on Microelectronic System Education, San Diego, ca., 3-4 june, 2007.