Signal Processing with GNU Radio

Jon Jacky

Magnetic Resonance Force Microscopy (MRFM)

Goal: molecular microscope, 3D images of individual molecules in situ

Marriage of atomic force microscope (AFM) and MRI imaging

RF coil (left), sample positioner (bottom), interferometer (top), cantilever (right)

Cantilever requires closed loop control: our GNU Radio application

MRFM Laboratory

MRFM Experiment Control Software

GNU Radio

GNU Radio technology stack

Integrated design from volts to GUI.

Developers are encouraged to program several layers (optimize across the whole stack).

GNU Radio hardware

Universal Sofware Radio Peripheral (USRP)

Available from Ettus Research LLC, but design is open source.

Newer USRP2 has 100 MHz converters, much larger Xilinx FPGA

Python programming

Connect signal processing blocks into a network and add a GUI.

Signal processing

Select signal processing blocks from the GNU Radio library.

Or, program your own in C++.

FPGA programming

Program the hardware on the USRP board.

FPGA: sea of logic gates and flipflops, your program connects them.

Design your own special-purpose computer (DSP or ...)

Jon Jacky