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RadxDealias dealiases doppler radar data.


RadxDealias reads input radar data from a file, dealiases the velocity data, and writes the results to a file.

Scientific Background

For more information on the James and Houze 2001 algorithm that RadxDealias is based on, please refer here.


The following items are required:

  • radar data (any Radx supported format, e.g., cfradial)
  • Sounding data
  • Parameter files for RadxDealias.

Parameter file

RadxDealias uses one parameter file that includes information about the files and dealiasing thresholds.

Ensure file is up to date

To obtain the default parameter file, use the following command:

/path/to/lrose/install/bin/RadxDealias -print_params > param_file_name

If you already have a parameter file and simply want to check for (and add) updated parameters while retaining current parameters, use the following command:

/path/to/lrose/install/bin/RadxDealias -params orig_param_file_name -print_params > new_param_file_name

Important parameters

Data input

  • input_dir: directory containing the data
  • mode: determines if the program waits for new files (REALTIME), moves through start and end times specified on the command line (ARCHIVE), or moves through list of files specified on the command line (FILELIST)

Output directory and file name

  • output_dir: files will be written to this directory

Process control

  • required_fields: dealiaser will not initialize without these files
  • delete_repeat_tilts: option to delete repeated tilts in volume
  • delete_tilt_decision: decide whether to keep recent or previous tilts if delete_repeat_tilts = TRUE

Dealiasing Parameters

  • nyquist_mps: nyquist velocity to override value in file

Sounding URL

  • sounding_url: url for sounding data in SPDB
  • sounding_look_back = time (minutes) to search back for a sounding
  • sounding_location_name = specify sounding name, otherwise all soundings in the database are considered valid

Running RadxDealias

To check all command line options for RadxDealias, including debugging options and file paths, type the following command into a terminal.

/path/to/lrose/install/bin/RadxDealias -h

Once your parameter file is complete, use a command similar to the following to run the application:

/path/to/lrose/install/bin/RadxDealias -params param_file_name

The user can also specify the location of cfradial files in the following manner:

/path/to/lrose/install/bin/RadxDealias -f /path/to/cfradial/files/ -params param_file_name