QZS L6 Tool: quasi-zenith satellite L6-band tool, ver.0.1.11

日本語

Summary

• This set of tools displays GNSS (Global Navigation Satellite System) messages and extracts specific formatted data from the raw data of GNSS receivers, for example, RTCM format and Michibiki L6 format.
• The suite consists of Python code that receives the messages via standard input, and the conversion results are sequentially outputted to the standard output. The use of standard error output is also possible as needed.
• It is designed to be used in conjunction with tools such as nc of netcat, and str2str of RTKLIB.
• Initially, it aimed to display the content of augmentation messages broadcasted by the quasi-zenith satellite Michibiki (QZS) in the L6 frequency band, including CLAS and MADO. However, it is now also capable of displaying Galileo HAS messages.
• Semantic versioning has been applied since 2024-08-11.
• Release note

Operating Environment

Prerequisites

You can run these tools in either of the following environments:

• Directly on Linux or macOS: Python 3.10 or later and pip are required. Run the tools from the command line.
• With Docker: A Docker environment capable of running Linux containers, such as Docker Desktop, is required. You can use the tools on Windows, macOS, Linux, and Raspberry Pi OS. The Docker image includes the Python runtime, nc, and str2str from RTKLIB 2.4.3 b34, so you do not need to install them on the host.

Setup

Installing from PyPI

To run the tools directly on Linux or macOS, install them with:

python3 -m pip install qzsl6tool

The required Python dependencies, including bitstring, galois, and numpy, are installed automatically. Install external command-line tools such as nc and RTKLIB's str2str separately as needed.

Cloning the repository (required for Docker builds or sample data)

Clone the repository with Git if you want to build the Docker image or use the included samples and tests. If you already have a clone, change to its root directory.

If you use the Windows Git CLI, apply the following setting before cloning to prevent CR characters from being added to Python line endings:

git config --global core.autocrlf input

git clone https://github.com/yoronneko/qzsl6tool.git
cd qzsl6tool

Setting up Docker

Build the Docker image from the root of the repository:

docker build -t qzsl6tool .

The image contains only the runtime and application code. It does not include Git, build tools, tests, or samples. To use the samples or tests, mount the host repository into the container as shown below.

Usage Examples

Running tools installed from PyPI

To display the included L6 sample, run the following command from the root of the repository:

qzsl6read.py < sample/2022001A.l6

If you have installed RTKLIB's str2str, you can display RTCM messages received via NTRIP:

str2str -in ntrip://ntrip.rnav.info.hiroshima-cu.ac.jp:80/OEM7 2>/dev/null | rtcmread.py

Running tools with Docker

To display the included L6 sample, run the following command from the root of the repository. The -v .:/mnt option mounts the host's current directory at /mnt inside the container.

docker run -it --rm -v .:/mnt qzsl6tool "qzsl6read.py < /mnt/sample/2022001A.l6"

To display RTCM messages received via NTRIP, run:

docker run -it --rm qzsl6tool "str2str -in ntrip://ntrip.rnav.info.hiroshima-cu.ac.jp:80/OEM7 2>/dev/null | rtcmread.py"

To display your own L6 data, run the following command from the directory containing the file. Replace my_l6_data.l6 with the actual filename.

docker run -it --rm -v .:/mnt qzsl6tool "qzsl6read.py < /mnt/my_l6_data.l6"

When handling GNSS binary data on Windows, keep input acquisition and the processing pipeline inside the container, as shown above. Do not pass binary data through cmd.exe or PowerShell pipes.

Testing the code inside the Docker image

Run the following command from the root of the repository to test the Python code inside the image using the tests and samples on the host:

docker run -it --rm -v .:/mnt -e CODEDIR=/root/qzsl6tool/python/ qzsl6tool "cd /mnt/test && bash do_test.sh"

Satellite Signal Display

RTCM Format Conversion

GNSS Receiver Data Conversion

Time & Coordinate Conversion

Directory Structure

├── c/               (contributed C source code)
├── dist/            (PyPI build artifacts; generated, not tracked by git)
├── docs/            (documentation directory)
├── python/          (Python source code directory)
├── sample/          (sample data directory)
├── test/            (test tool directory)
├── typings/         (local type stubs for pyright/Pylance)
├── CLAUDE.md        (documentation for Claude)
├── Dockerfile       (Docker image production procedure)
├── license.txt      (license description)
├── pyproject.toml   (configuration for PyPI)
├── readme-en.md     (this file, English document)
├── readme.md        (Japanese document)
├── release_note.md  (release note)
├── requirements.txt (declaration of Python package dependencies)
└── SECURITY.md      (description of reporting security vulnerabilities responsibly)

License

This project is licensed under the BSD 2-clause license.

Users are permitted to use this program for commercial and non-commercial purposes, with or without modification, but this copyright notice is required. The function rtk_crc24q() in librtcm.py utilizes the achievements of RTKLIB ver.2.4.3b34.

Copyright (c) 2022-2026 by Satoshi Takahashi
Copyright (c) 2007-2020 by Tomoji TAKASU