gr-pdw: GNU Radio Pulse Descriptor Word (PDW) Blocks

This module contains blocks to generate pulse descriptor words (PDW) in GNU Radio. PDWs are measurements of pulse properties and can include:

• Pulse width
• Pulse power
• Pulse frequency
• Time of Arrival
• Polarization
• Pulse Angle of Arrival
• Many others

Pull requests are very welcome as well as feature requests and bug reports.

Quick Start

Dependencies required:

• GNU Radio
• UHD: For PDW Generation from SDR
• h5py: Logging PDW measurements to file

To install from source:

$ git clone https://github.com/gtri/gr-pdw
$ cd gr-pdw
$ mkdir build; cd build
$ cmake ..
$ make
$ make install

Steps may vary slightly depending on how your particular GNU Radio environment is setup.

Contents

• Blocks
  • pulse_detect: Performs pulse detection and tags start/stop of pulse.
  • pulse_extract: Extracts pulse I/Q and makes pulse measurements
  • pdw_to_file: Writes PDW measurements to file.
  • pdw_plot: Real time plots of PDW measurements
  • usrp_power_cal_table: Gain calibration for USRP pulse power measurements.
  • virtual_power_cal_table: Virtual gain calibration of simulated PDW flowgraphs.

SDR Support

gr-pdw is agnostic to the SDR being used in UNCALIBRATED modes. That is, pulse power measurements will be in units of dBfs instead of dBm.

For CALIBRATED pulse power measurements, gr-pdw has been tested with the USRP B2xx series SDR. A calibration table is provided for these SDRs.

Examples

Flowgraphs

gr-pdw/apps

• virtual_pdw.grc

  • Simulated pulse generation and measurements.

• usrp_pdw.grc

  • PDW measurements with a USRP B210 SDR

Hier Blocks

gr-pdw/examples

• pulse_gen_heir.grc
  • Generates pulses based on input pulse width, pulse amplitude, and pulse repetition interval (PRI)

Scripts

gr-pdw/examples

• read_pdw_file_example.py
  • Example script to read PDW file in hdf5 format.
• test_pdw.hdf5
  • Example PDW file

Roadmap

• Port blocks to C++ to improve performance with regards to sample rate, long pulse, and high PRI scenarios
• Improved plotting / visualization tools
• Improved PDW file manipulation tools
• Modulation detection
• Pulse I/Q data export
• PDW Streaming over a network
• Firmware / RFNoC PDW Generation (High bandwidth or embedded modes)
• PDW Replay