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

Increasing number of wireless standards GPS, Cell Phone

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)?

Spectrum space as a scarce resource

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

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.

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. www.sdrforum.org

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.

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

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)

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)

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

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

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

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

SDR Architecture

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

Development Boards

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.

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

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

Deep Space Communications THANK YOU