1. SOFTWARE DEFINED RADIO
A STUDY
AMSAT SA CONFERENCE
Pretoria
29 May 2016
Deon Coetzee ZR1DE

2. Increasing number of wireless standards
GPS, Cell Phone

3. The Problem Myriad standards exist for terrestrial communications
Cell phone communication standards change every few years
Satellite ground station would like to listen to multiple spacecraft, some launched in the 1970s
Spectrum space is a precious resource
Each frequency is “owned”
How do we deal with new technologies like ultra wide band (UWB)?

4. Spectrum space as a scarce resource

5. Software-Defined Radio
The Solution?
Flexible radio systems that allow communication standards to migrate
Flexible methods for reconfiguring a radio in software
Flexible, intelligent systems that communicate via different protocols at different times
Software-Defined Radio

6. What is 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.

7. Software-Defined Radio SDR Forum
Radios that provide software control of a variety of modulation techniques, wide-band or narrow-band operation, communications security functions such as hopping, and waveform requirements of current and evolving standards over a broad frequency range.

8. 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
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.
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.

9. Software Defined Radios consist of
Programmable gate arrays
Digital Signal processors
General processors
An antenna
A digital to analog converter and an analog to digital converter

10. Tier 0: Hardware Radio (HR) No changes to system can by done by software
Antenna RF IF
Baseband
ADC/DAC DSP
Bandpass Filter
Variable Frequency Oscillator
Local Oscillator (fixed)

11. Tier 1: Software-Controlled Radio (SCR)
Control functionality implemented in software.
Modulation and frequency in hardware
Antenna RF IF
Baseband
ADC/DAC
DSP
Local Oscillator (fixed)

12. Tier 2: Software-Defined Radio (SDR)
Antenna RF IF
Baseband
ADC/DAC
DSP

13. Tier 3: Ideal Software Radio (ISR)
Prior to A/D-conversion and after D/A conversion
No analog amplification
No heterodyne mixing

14. Tier 4: Ultimate Software Radio (USR)
Software radio in a chip
Wide range of adaptive services
For comparison purposes rather than implementation

15. Future: Shift from Tier 0 to 4
Anil Shukla, Qineti

16. SDR Architecture

17. SDR Platforms
Wind River VxWorks 6.2 Commercial Grade Real-Time Platform
Xilinx Virtex-II Platform FPGA
Texas Instruments TMS320C6713 DSP
Sundance’s SMT8096 platform
The SMT8096 is a rapid-prototyping solution package, comprised of an SMT310Q PCI Carrier hosting SMT395 DSP and SMT350 ADC/DAC modules.
Altera’s Stratix Professional Edition
It includes a Stratix II DSP development board, the DSP Builder design tool, Quartus II development software, MATLAB/Simulink evaluation software, evaluation intellectual property (IP) cores

18. Development Boards

19. Looking Ahead Smart Radios Cognitive Radios
that configure themselves to perform the communications task requested.
Cognitive Radios
that learn about their environment (e.g., other users nearby, interference, location, elevation) to optimally configure themselves.

20. Evolution of Cognitive Radio
Enables
Enables
Spectrum Deregulation
Software-defined Radio
Drives

21. THE INVESTIGATION CONTINUEs
WILL THE DEVELOPMENT OF FLEXIBLE MODULES CREATE A PLATFORM FOR A NEW BREED OF RADIO AMATEUR EXPERIMENTER?

22. Deep Space Communications
THANK YOU