t he software defined radio team
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T he Software Defined Radio Team. D. J. Love, C.-C. Wang, and J . V. Krogmeier School of Electrical and Computer Engineering Purdue University, West Lafayette January 12, 2011. Software-Defined Radio. Ideal SDR Connect Antenna to an ADC/DAC Sampling frequency limitation in RF - PowerPoint PPT PresentationTRANSCRIPT
The Software Defined Radio Team
D. J. Love, C.-C. Wang, and J. V. KrogmeierSchool of Electrical and Computer EngineeringPurdue University, West Lafayette
January 12, 2011
Software-Defined Radio
Ideal SDR• Connect Antenna to an ADC/DAC
• Sampling frequency limitation in RF• Dynamic range limitation
Practical SDR• Tunable RF Front-end implemented in
hardware• All digital signal processing in software
VIP has two SDR platforms• Ettus Research, LLC + GNU Radio• Rice WARP + Matlab
GNU Radio / USRP Hardware
GNU Radio• Open source software• Provides APIs for flexible PHY and MAC
support• Based on C++/Python programming
Universal Software Radio Peripheral (USRP) by Ettus• Designed to work with GNU Radio• Combination of
Various RF front-ends daughter boards (0-100MHz, 400MHz, 900MHz, 2.4GHZ)
ADC / DAC with data rates up to 64 MSample/sec
All DSP functions in software on general-purpose CPU (PC)
Spring 2011: Four Possible SDR Projects
Power Line Communications (PLC) Interface and SDR Software for MIMO PLC Channel Sounding
FM Transmitter for iPod Using Radio Broadcast Data System (RBDS) to Display Playlist Information
Software Defined FM Receiver for Inductive and Magnetic Vehicle Detectors
Spectrum Sensing and Modulation Classification for Cognitive Radio
Power Line Communications (PLC) Interface and SDR Software for MIMO PLC Channel Sounding
FM Transmitter for iPod Using Radio Broadcast Data System (RBDS) to Display Playlist Information
Software Defined FM Receiver for Inductive and Magnetic Vehicle Detectors
Micro-loops: magneticfield sensors
Inductive-loops: eddycurrent sensors
Micro-Loops and Inductive Loops Appear as Variable L: Measured as Change in Oscillator Frequency
Example Signatures fromI-70 W Near Indy Airport
SDR FM Demodulator for Loop / Micro-loop Signature Logger
Available Hardware is Inadequate for Research• Uses proprietary interface and unknown signature
demodulation algorithms• Very limited ability to change “carrier” frequency• Relatively low sensitivity• Not programmable
Desired capability• Experiment with different FM demodulation algorithms
in order to improve sensitivity• Explore classical FM bandwidth vs. demodulated SNR
tradeoff• Use improved receiver sensitivity to reduce the required
aperture size in inductive loop sensors – lower power and more detailed signatures
• Address self-interference issues that are common in current systems