cr2016-L1.ppt Cognitive radio for wireless

Cognitive radio

1. The future of wireless technology

2. Software Defined Radios what are they??
A radio in which some or all of the physical layer
functions are software defined.
This is contrasted with older radios where all of their
functionality is determined by hardware.

3. 3
Levels of SDR
Tier Name Description
Tier 0Hardware Radio (HR)
Implemented using hardware components.
Cannot be modified
Tier 1
Software Controlled
Radio (SCR)
Only control functions are implemented in
software: inter-connects, power levels, etc.
Tier 2
Software Defined
Radio (SDR)
Software control of a variety of modulation
techniques, wide-band or narrow-band
operation, security functions, etc.
Tier 3
Ideal Software Radio
(ISR)
Programmability extends to the entire system
with analog conversion only at the antenna.
Tier 4
Ultimate Software
Radio (USR)
Defined for comparison purposes only

4. Five Tiers of SDR technology
Tier 0 –Pure hardware radios
Tier 1 –Software “controlled radios
Tier 2 -modulation methods, band selection between
wide or narrow, security mechanisms and controls
such as hopping pattern management, and wave form
selection are all handled by software

5. Four Tiers Cont.
Tier 3 –fully programmable radios.
Tier 4 -radios are the absolute model of
perfection, and they exist only on paper. They are
the absolute pinnacle of anything wireless
technology could ever even begin to approach.
These radios are capable of anything a user can
imagine, from storing money transfer information
on smart cards, to receiving satellite transmissions
in real time.

6. The history of SDR
SPEAKeasy phase I
A government program with the following goals:
1.) to develop a radio that could function anywhere
between 2 Mhz and 2 Ghz,
2.) to be able to communicate with the radios used by
ground forces as well as air force and naval radios in
addition to satellites
3.)to develop a new signal format within 2 weeks with no
prior preparation
4.) to use parts and software from multiple contractors at
once

7. SPEAKeasy Phase I
When the project was tested at TF-XXI Advanced
Warfighting Exerciseit was deemed a success.
One problem was that the cryptography engine could
not keep up well enough to maintain several
connections at once.

8. SPEAKEasy Phase II
Phase II made use of an open architecture known
as Software communication architecture.
This phase of the project was focused on refining
the phase one project for use in the field,
minimizing the device form factor and getting the
system ready for use in the field.
15 months since the start of the project a fully
functioning radio was produced.
It was so successful that no further development
was needed.

9. Phase II Cont
This radio only had a range between 4 MHz and 400
MHz
data rates between 75 bps and 10 Mbps.
22 different wave forms in addition to GPS and cellular
communications.
four channels programmed into it at once as well as
cellular and GPS at the same time.

10. A final contributor Joint Tactical Radio
System
Unlike the other projects that ran from 1992-1995,
JTRS was started in 1998.
Goals: to create a radio that will work in harmony
with many different other radios, both civilian
and military, built in encryption, and wideband
networking software to allow the system to form
ad hoc wireless networks.
The key architecture used in this projected is the
Software Communications Architecture(SCA).

11. Software Communications Architecture

12. SDR What does it take to make one?
Software Defined Radios are made up of:
programmable gate arrays
Digital Signal processors
General processors
An antenna
A digital to analog converter and an analog to digital
converter

13. How do they work?
In the case of a receiver
The antenna receives a signal and passes it through
the analog to digital converter.
The result from the converter is passed to the
digital signal processors.
The software is left in charge of every other
function for establishing and maintaining a
connection, such as modulation/demodulation,
frequency selection, and encryption.
A transmitter simply works opposite to the way a
receiver does.

14. One Example

15. SDR, Why Use It?
Flexibility
Can be updated on the fly
Interoperability
Easier to upgrade by a non-technician using an update
bundle.
Minimal infrastructure requirements for use in the
field
Effective for setting up ad-hoc networks

16. SDR the downsides
SDR is often referred to as a silver bullet to many
networking problems without any attention being
paid to the effort involved.
For example, the problem with trying to set up a
single unifying network.
The competitor’s paradox.
The potential for knocking out other networks
with accidental misconfiguration by a user.
Problems with multiple service levels, and fraud.

17. Downside Cont
Security Issues in:
Authentication
Authorization
Misuse
Verification of validity of software updates

18. Downsides Cont
Implementation and switchover costs:
The upfront unit costs are higher than with ordinary
hardware radios.
Sometimes customers pay for more flexibility than
they actually need.
The sunk cost associated with legacy equipment that is
no longer used

19. Limited advancement
Even with Software Defined Radio technology
advancing rapidly, many of the technologies it is built
upon are not advancing nearly as quickly.
Moore’s law has helped immensely with processing
and memory.
Limits on front-end technologies and RF capabilities.

20. Where could SDR technology Lead?
•The ultimate potential of SDR technology is realized within adaptive
array antennas.
•These intelligent antennas first must detect which direction a signal is
coming from, and then adapt its radiation pattern to allow for optimum
communication conditions through the use of beam forming.
•Beam forming is using several antennas together to utilize constructive
interference to generate an approprate radiation pattern
•SDR technology allows a radio to be controlled entirely by software,
from this point, system learning and algorithms can be introduced into
the radios using methods already applied in artificial intelligence

21. MIMO
Multiple Input Multiple Output devices.
These are a class of intelligent antenna.
This type of device uses an array of intelligent
antennas at both ends of the link. This will allow both
the sender and the receiver to adapt to changing
environmental conditions and ultimately to create the
optimum communication environment.

22. What is SDR?
SDR-Software Defined Radio is a general term
referring to any radio design that uses a computer
and some controlling software to “define” that
radio’s operation.
Most of today’s ham rigs incorporate at least some
level of software definition of their operational
modes.
A true SDR has very little hardware and virtually
every aspect of its operation is performed by the
controlling software.

23. The SDR-IQ
So, what makes it work? It uses the latest in DSP
technology to make a receiver (only) that works
from 50kHz to 30MHz in “chunks” as large as
192kHz. Very few components in the unit, mostly
the DSP chip.
The software (SpectraVue from the mfr, lots of
other stuff out there) defines the filters, the
frequency coverage, the mode (USB, LSB, CW, FM,
etc), the attenuators, etc.

24. Some Of The SDR’s On The Market
Flex Radio-the Flex 5000, 3000, 1000 and now 1500-
transceivers with varying levels of sophistication.
RFSpace-SDR-IQ, SDR-14-receivers with superior
performance and features.
SoftRoc-Simple, small single-band receivers offering a
great intro into SDR’s for $20-$50.
HPSDR-transceivers offering varying levels of
sophistication and features, depending on what options are
purchased and how the builder configures them.
Numerous others; do a Google search on SDR for a
surprisingly long list. Also refer to QST, there have been a
number of reviews of them.

25. So, WHY an SDR?
The biggest reason to have a Software Defined
Radio is the flexibility it offers the user.
Filtering can easily be changed, depending on the needs
Modes of operation can be changed to accommodate
new communications technologies
All of these functions are controlled in Software, rather
than Hardware, making changes simpler (no new
filters/hardware demodulators required-the code takes
care of it)

26. So, WHY an SDR? (cont’d)
One of the biggest features is the ability to “look at” or view
a chunk of the radio spectrum, all frequencies at the same
time, to find stations or places to operate.
The SDR-IQ can look at as much as 192kHz of the spectrum
at any time, making the unit a useful “Panadaptor”, when
connected to the station antenna. Using the supplied
software, it can also be used to control the “real” station
transceiver when selecting stations to work.
SDR’s can also output the recovered signals to a PC and
thus, chunks of spectrum can be stored as .wav files and
replayed later for analysis.

27. Links to some SDR Suppliers
RFSPACE (SDR-IQ, SDR-14): www.rfspace.com
Flex Radio systems (Flex 5000, 3000, 1500, 1000):
www.flex-radio.com
SoftRock Radio (SoftRock 40, 20, etc):
www.softrockradio.com
HPSDR (“kit” form SDR’s): www.hpsdr.org

28. What Software Is Available?
There is quite a bit out there, more being written every day.
In addition to the software supplied with the various
radios, two very good programs are: LINRAD (written for
Linux os) and WINRAD (similar software, written for
Windows-based systems). New is SDR-IP, which will
interface the new RFSPACE radio via IP to the computer.
There is plenty of good code out there for users of the Flex
radios, the SoftRock’s, and the HPSDR’s, enabling many
new modes and functions. I suggest joining one or more of
the SDR forums for the latest info and evaluations of
software.

29. So Let’s Look At A Receiver Screen
Using Spectravue

30. And Another

31. In Conclusion
Software Defined Radios employ a technology that will ultimately
bring a great deal of flexibility and adaptability to the networks of the
future.
As many benefits as they provide, the technology still has a long way to
go before it finds its way into cellular handsets that can exploit the
absolute potential of SDR.
SDR serves as an enabling technology for intelligent radios and MIMO
devices.

32. Any Questions?

33. Sources
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Website:http://en.citizendium.org/wiki/Software-defined_radio.
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from SDR Forum Website:http://www.sdrforum.org/pages/documentLibrary/documents/SDRF-06-P-0001-
V1_0_0%20_Public_Safety.pdf.
, S&A-SEC, . (2006). System Security. Retrieved 9 December 2008, from SDR Forum
Website:http://www.sdrforum.org/pages/documentLibrary/documents/SDRF-02-P-0006-V1-_0_0_System_security.pdf.
, SDR Forum, . (2008). What is SDR?. Retrieved 7 December 2008, from
Website:http://www.sdrforum.org/pages/aboutSdrTech/whatIsSdr.asp.
, SPAwarSystems Center San Diego, . (2008). Software Communications Architecture downloads. Retrieved 7 December 2008,
from The US Navy Website:http://sca.jpeojtrs.mil/downloads.asp?ID=2.2.2.
, The Department of Homeland Security, . (2008). Safecom. Retrieved 9 December 2008, from The United States Government
Website:http://www.safecomprogram.gov/SAFECOM/.
, The Institute for Telecommunications Sciences, . (2008). the history of SDR. Retrieved 9 December 2008, from
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, Wikimedia Foundation Inc, . (2008). Software Defined Radio Wikipedia. Retrieved 7 December 2008, from GNU Licensing
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Website:http://en.wikipedia.org/wiki/Multiple-input_multiple-output_communications.
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