marsis 0.0.8

An open source processor for the MARSIS instrument on Mars Express

marsis

Open-source processor for the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS)

This software implements several processing routines that, when performed in sequence, transform a MARSIS Experimental Data Record (EDR) into an interpretable data product (a "radargram"). The following processing steps are currently implemented:

1. Parsing of EDR label files
2. Parsing of EDR science and auxiliary data files
3. Decompression of science data
4. Several modes of ionosphere compensation
   • No ionosphere compensation
   • Ionosphere compensation via:
     • "Campbell method" (https://doi.org/10.1002/2015JE004917)
     • "McMichael method" (https://doi.org/10.1109/RADAR.2017.7944326) <> - "Italian method" (https://doi.org/10.1109/RADAR.2008.4720760) <> - Dual band range compression with ionosphere compensation that is a hybrid of the Smithsonian and Italian methods
5. Range compression

The processor can be used as a command line tool or within a Python script to generate MARSIS radargrams and/or output metdata from the EDR files in a text format.

The Campbell method requires a global DEM of Mars, I recommend using this one:
https://mchristo.net/data/megr_32ppd.tif (253 MB)

Currently there are two command line tools included in the package:
marsis_download.py - Script to download a list of MARSIS EDRs
marsis_processor.py - Script to process a single MARSIS EDR

Usage instructions can be printed to the terminal with marsis_download.py --help and marsis_processor.py --help

Useful links

MARSIS Planetary Data System (PDS) Page - https://pds-geosciences.wustl.edu/missions/mars_express/marsis.htm

Useful information

MARSIS sampling frequency - 2.8 MHz
Effective sampling frequency in data files after I/Q conversion - 1.4 MHz
Chirp center frequencies - 1.8, 3, 4, and 5 MHz
Chirp bandwidth - 1 MHz
Chirp duration - 250 μs
Chirp center frequency in EDR files - 0.7 MHz