Abstract
The aim of the project is to build a wireless transceiver, which will be capable of transmitting
and receiving data at high speeds, using the 5.7 GHz ISM band. The concept of the
transceiver will be that of RF systems using the IF from “software radio”. Students have
already done testing on 5.7 GHz band, however they did not use software radio. Also, the
testing was done on a board on which all components were laid out. Our aim is to use the
“surface mount” counterpart and lay them on a printed circuit board.
The project requires the team members to have an understanding of RF systems-the basic
knowledge of how data transmission takes place in a radio system. In order to be able to
generate data and also for programming the software radio, knowledge of visual basic is
required.
By the end of the project, we will be delivering a compact, high performance, cost effective
5.7 GHz transceiver capable of high data transfer with precision. Data will be in the form of
binary, audio or video. The transceiver will be using the IF signal using the software radio.
1
Project Proposal plan
Introduction
Wireless communications have been growing since a few decades now, and have become
extremely popular since Bell Labs developed the concept of cellular during 1960-1970.
Various applications use wireless technology such as cell phones, satellite communication,
etc. Since there has to be a restriction on what bands people can use to transmit, IEEE has
divided the frequency bands.
The bands available us for making the transceiver are 915 MHz, 2.4 GHz and 5.7 GHz.
These are also known as ISM bands. The 915 MHz and 2.4 GHz bands are already being
used for various applications and thus there is a need to move to a higher band – 5.7 GHz.
There has been on going research on this topic. At Stevens itself, research assistants and
students built a tri band RF testbed. This testbed was capable of being switched between the
three ISM bands. One of the problems with this design was that it was really bulky and is
limited to research in school.
Our model is similar to the previous project, however we will replace the parts of the testbed
with there surface mount counter parts. This will be made on a 10cm x 4 cm printed circuit
board.
2
Design Requirements
Our aim is to deliver a printed circuit board that can transmit and receive at 5.7 GHz and
integrating the software radio.
The main components which we will require include:

Voltage Control Oscillator: As the name suggests, it is an oscillator which outputs
frequency based on the voltage supplied.

Frequency Doubler: A component used in RF systems which outputs double the
frequency that is input.

Frequency Mixer: A device used to add/subtract 2 different frequencies.

Amplifier: Strengthens the signal. When a signal passes through so many sages,
there is lot of power loss and noise that gets added to it. An amplifier boosts the
signal by raising its power level.
On the following pages, specifications are explained for the components which we shall be
using for the project.
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Specifications for the parts used:
Voltage Control Oscillator: JTOS-3000
Operating Frequencies:
Power Output:
Power required:
Cost:
2300 MHz- 3000 MHz
+10 dB
5 Volts
$20
Tentative designs for Surface Mount Frequency Multiplier – Doublers.
Frequency Doubler- KBA-40
Manufacturer: Mini-circuits
Input Frequency:
Output Frequency:
RF input power:
Conversion Loss:
Cost:
2700 MHz-4800 MHz
5400 MHZ- 9600 MHz
10-16 dBm
15 dB
$14.95
Frequency Doubler- FX-06
Picture not available
Manufacturer: Pulsar Microwave
Input Frequency:
Output Frequency:
RF input power:
Conversion Loss:
Cost:
300 MHz- 3000 MHz
600 MHz- 6000 MHz
10-16 dBm
13 dB
NA
4
Frequency Mixer: SKY-60
Manufacturer: Mini Circuits
LO/RF Frequency:
IF:
Conversion Loss:
2500-6000 MHz
DC-1500
6.2 dB
Amplifier: ERA-2
Manufacturer: Mini Circuits
Frequency (GHz):
Gain:
Operating Power:
DC-6
12 dB
3.4 Volts
5
Software Radio :
There has been an ongoing transition from analog to digital signals in the communications
world. As a result of this the functions of a modern radio are being defined in software. The
modulation channel waveforms of such a radio are defined in software. Waveforms are
generated as sampled digital signals, converted from digital to analog via a wideband DAC
and then possibly up converted from IF to RF. The receiver, similarly, employs a wideband
Analog to Digital Converter (ADC) that captures all of the channels of the software radio
node. The receiver then extracts, down converts and demodulates the channel waveform
using software on a general-purpose processor. Software radios employ a combination of
techniques that include multi-band antennas and RF conversion; wideband ADC and Digital
to Analog conversion (DAC); and the implementation of IF, baseband and bitstream
processing functions in general purpose programmable processors.1
1
http://ourworld.compuserve.com/homepages/jmitola/whatisas.htm
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Design Approach
The new model will definitely improve the quality and quantity of data being transmitted.
The main reason is that conversion loss at each stage is less compared to what was used in
the previous design for 915 MHz and 2.4 GHz. This can be justified by the small size of all
parts (since this is PCB lay out). There will be no power loss because the wires connecting
the parts together will be thinner and smaller.
Another aspect that makes our project unique is that we are using software radio to provide
the IF signal. Apart from that, the sound card performs the functions such as analog to digital
and digital to analog conversion. The software used to run the “software radio” does the
modulation and demodulation.
Although no calculations or experiments have been performed, we expect an improved bit
transfer rate (up to 11MBps), on the basis of our research.
In terms of cost, this model is way more cost effective. There is a tremendous difference in
the cost of the previous testbed (which used plug-in and coaxial components) and the current
PCB model. Roughly, the cost of making the PCB is 300% less than that of testbed.
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PCB Layout :
Modulation of signal
Tuning of VCO
Software
Radio
IF=50 Hz
2 x 2850 = 5650 MHz
VCO
JTOS-3000
Frequency
Doubler
Frequency
Mixer
Amplifier
5.7 GHz signal generated
TRANSMITTER
2
3
Demodulation of signal
Tuning of VCO
Software
Radio
5.7 GHz signal
received
VCO
Frequency
Doubler
Frequency
Mixer
Amplifier
Receiver
4
2
As of now, we are not sure which model for the amplifier and frequency mixer we shall be using, therefore coming up
with noise figure calculations may not be possible at this point.
3
4
The pin connections are not the same as actual connections.
The external power supplies are not shown in the diagrams.
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Approach for Software Defined Radio- Source Code
The original source code for the Software defined radio model includes all required
frequency modulation/demodulation schemes for most frequency band types i.e. Frequency
Modulation and Amplitude Modulation but we will write the Phase Shift Key algorithm for
the SDR-1000 software. Once this algorithm is constructed, we will be able to generate
different binary outputs and transmission rates by making all the necessary calculations for
the 900Mhz, 2.4 GHz and 5.7 Ghz respectively.
Different Steps that will need to be modified in Visual Basic:

Construct array as a placeholder to take in frequency inputs generated by the Wireless
Testbed into the external sound card for frequency band processing.

Generate sine wave shifting once binary inputs change binary value from 0 to 1 and
vice-versa. This portion will include amplitude calculations for all three different
frequency rates.

Modify modulation and demodulation source code to incorporate the PSK case in
SDR-1000 software thus allowing binary transmission using PSK format.

Generate Output Display to provide visible model of frequency transmission and data
rate for all frequency rates.
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Other Possible designs:
Use of a Frequency Tripler instead of a Doubler:
As the name suggests, the tripler three folds the input frequency. It has been used before by
Stevens’s students. One of the drawbacks of using a tripler is that there are not many choices
available for surface mount models. Stability is another factor. Triplers are very sensitive to
the slightest change in voltage and therefore they can burn off. They are also expensive
compared to doublers.
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Financial Budget
· Materials and parts
Materials list for
your product
Modulator
Voltage control
Oscillator
Frequency mixers
Soldering
equipment
Print Circuit Boards
No. of
Lot Pieces per
Size
Unit
500
500
500
5
250
500
500
Amplifiers
Frequency
multiplier
Cost per Unit ($)
Total
Cost
2
49.95
99.9
2
30
60
2
39.95
79.9
1
20
20
1
2
15
91.95
15
183.9
2
14.95
29.9
Total Material
Cost ($) per unit
488.6
References:
Parts List:
Modulators, Frequency Mixers, Multipliers :
VCO:
Soldering:
www.mini-circuits.com
www.maxim-ic.com
· Labor/Support Staff costs
# of
Individuals
Process or Job Description
Annual (yr)
Salary per
individual
Total $ K
Receiving, Incoming test
1
$30,000
$30,000
Final test
1
$30,000
Per per
$30,000
Packaging/ Shipping
1
$25,000
$25,000
Materials Handling
1
$30,000
$30,000
V.P. Manufacturing
1
$40,000
$40,000
Department Managers
2
$35,000
$70,000
Manufacturing Staff & Engineers
2
$32,000
$64,000
Other
(1) Total Factory Overhead Cost
$289,000
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· Profit Margin per unit ($)
Unit cost
750.00
Unit price
500.00
Profit margin
250.00
· Test equipment
Parts to be used in the lab
# of
parts
Cost/unit
Cost($)
signal generator
volt-meter
soldering equipment
1
2
2
65280
15
20
65280
30
40
Spectrum Analyzer
Cables
Multiple Power Supplies
connectors
Total
1
4
2
3
25627
15
1000
10
25627
60
2000
30
93067
References
http://we.home.agilent.com/USeng/nav/12032.0/pc.html
http://we.home.agilent.com/USeng/nav/14407.536894440/pd.html
www.agilent.com
· Documentation costs
No.
Units
Equipment List for General Office
$ / Unit
Total ($)
References
Office Equipment
Personal Computers
15
500
7500
Cubicle Desk Units
15
150
2250
Office Chairs
30
100
3000
IKEA
IKEA
Multi-function Copiers
2
1000
2000
OfficeMax
Fax Machines
1
200
$
200
OfficeMax
Projectors
1
600
600
OfficeMax
Whiteboards
15
100
1500
1
1000
1000
Conference Room Tables
F-5 Total Office Equipment
18,050
12
CompUSA
IKEA
IKEA
· Rent, utilities, overhead
No. of
persons
(A) Sq. Ft.
/person
128
64
128
64
150
150
19.2
9.6
Packaging
1
1
0
1
1
1
64
64
64
64
64
64
150
150
150
9.6
9.6
9.6
Materials Handling
0
V.P. Manufacturing
1
2
2
1
96
64
64
64
96
128
128
128
150
150
150
150
14.4
19.2
19.2
19.2
Process or Job Description
Receiving, Shipping
R & D, Incoming test
Fabrication
Assembly
Final test
Department Managers
Manufacturing Staff & Engineers
Sales/ finance
Total
Sq.Ft.
(B) $ / Sq.
Ft.
864
Subtotal
259.2
0
259.2
Add Hallways (30% of subtotal)
Add Stairwells (30% of subtotal)
Add Common area (30% of subtotal)
110.4
150
38.88
150
38.88
1382.4
F-1 Total Plant Cost
Total ($K)
188.16
(A) 200 sq.ft – small office; 300 sq. ft – medium office; 500sq.ft – large office
(B) Office cost $/sq.ft: $200-$300/sq.ft
This manufacturing plant/corporate office will consist of 15 phone lines($40/month)
and electric bill of $2000 monthly.(Estimate based on size and equipment). Our project will
be demonstrated at our corporate offices, avoiding any additional expenses such as traveling.
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14
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Conclusion
The objective for this project is to provide a method where RF signals can be combined with
IF signals of Software Defined Radio. The possibilities are endless for Software Defined
Radio considering that any two entities will be able to transmit information across different
frequencies and have there own specified modulation techniques. The intent of the project is
to combine both a hardware specified Wireless Testbed model that will generate a 5.7 GHz
frequency and use it to transfer data in the form of several Frequency Band types such as
Frequency Modulation, Amplitude Modulation and Phase Shift Key Modulation which will
be performed by the Software Defined Radio.
We will deliver a compact high performance transmission unit functioning at 5.7 GHz. In
future, we would like to embed the other two ISM bands – 915 MHz and 2.4 GHz on the
same unit. The three different frequency bands combined will provide different options for
data transmission. This project has evolved from other successful research projects and
therefore proving that this concept is feasible and modifiable for further development.
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References
Triband RF Transceiver Webpage, [Online], 10 Aug 2004-last update,
Available: http://www.stevens.edu/wireless/triband/[10 Sept 2004]
Experimentation of Adaptive Communications using Flex-radio Webpage, [Online], 14 May
2004-last update, Available: http://www.stevens.edu/wireless/flexradio/[2 Oct 2004]
G. Youngblood, AC5OG, “A Software-Defined Radio for the Masses: Part 1,”
QEX, July/Aug 2002, pp 13-21
M.E. Frerking, Digital Signal Processing in Communication Systems (New York: Van
Nostrand Reinhold, 1994, ISBN:0442016166), pp 272-286.
G. Youngblood, AC5OG, “A Software Defined Radio for the Masses, Part 2,” QEX,
Sep/Oct 2002, pp 10-18.
G. Youngblood, AC5OG, “A Software Defined Radio for the Masses: Part 3,” QEX,
Nov/Dec 2002, pp 27-36.
G. Youngblood, AC5OG, “A Software Defined Radio for the Masses: Part 4,” QEX,
Mar/Apr 2003, pp 20-28.
SDR-1000 General overview and component breakdown Webpage, [Online], 15 March
2004-last update, Available: http://flex-radio.com/ [27 Sept 2004]
Software Defined Radio - Senior Design Project for 2003-2004 Webpage, [Online], 30
March 2004-last update, Available: http://koala.ece.stevens-tech.edu/sd/archive/03F04S/websites/grp6/index.htm
Visual Basic Tutorial Webpage, [Online], 8 June 2003-last update, Available:
http://www.vbtutor.net/ [15 Oct 2004]
Components for Wireless Testbed Webpage, [Online], 25 Oct 2004-last update,
Available: http://www.mini-circuits.com/ [10 Oct 2004]
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