AIS Simulator

An AIS simulator based on AIS BlackToolkit from Trendmicro.

This code provides three GNURadio blocks. Two for AIS frame generation from a given bit string and a websocket server to PDU message converter.

The web application let you select and compose various AIS message and performs conversion to the required bit string that is then send via websocket connection to the GNURadio backend.

Tested in the following environments:

• GnuRadio 3.10.9.2, gr-osmosdr 0.2.5, Ubuntu 24.04 noble, Python 3.12.3, GNU C++ 13.3, Boost 1.83, HackRF One (2023.01.1)

Building

Dependencies

You need to install the following build dependencies first:

Ubuntu 20.04 focal and earlier (Python 2 based toolchain):

sudo apt-get install -y \
    cmake \
    autoconf \
    libtool \
    pkg-config \
    build-essential \
    python-docutils \
    libcppunit-dev \
    swig \
    doxygen \
    python-scipy \
    python-gtk2 \
    gnuradio-dev \
    gr-osmosdr \
    libosmocore-dev

Debian 11 bullseye / Ubuntu 22.04 jammy / Ubuntu 24.04 noble (Python 3 based toolchain, matches the tested environments above; same package names hold across all three):

sudo apt-get install -y \
    cmake \
    autoconf \
    libtool \
    pkg-config \
    build-essential \
    python3-docutils \
    libcppunit-dev \
    swig \
    doxygen \
    python3-scipy \
    gnuradio-dev \
    gr-osmosdr \
    libosmocore-dev

Build & Installation

See README on how to build and install the custom GnuRadio block.

Note: gr-ais_simulator blocks need to rebuild and installed after GnuRadio toolchain update.

Web application

The web UI is written in TypeScript and compiled to webapp/assets/, which is checked into the repository. TypeScript is a pinned devDependency (5.9.3 as of this writing — npm's latest tag has moved to TypeScript 7, which enables stricter type-checking by default and will not build this project's non-strict code). Install it once, then rebuild the compiled output after editing any file under webapp/*.ts:

npm install
npm run build

Tested with Node.js 24.14.1 / npm 11.11.0.

How to run

1. Start AIS simulator $ python3 -u ais-simulator.py
2. Open ./webapp/ais-simulator.html in browser.
3. Select AIS message type, modify parameters and send message...

Tested against rtl_ais, Comar Systems CSA300 and Saab R5A class A AIS transponder via over the air transmission.

Command line options

Run python3 ais-simulator.py --help for the full list. The most commonly used options:

Option	Description	Default
--channel {A,B}	AIS channel: A = 161.975MHz (87B), B = 162.025MHz (88B)	A
--addr	Websocket server listen address	0.0.0.0
--port	Websocket server listen port	52002
--sampling_rate	Sampling rate, must be at least 2x the bit rate	8000000
--bit_rate	Bit rate in Baud	9600
-a	Enable RF amp	disabled
-l GAIN	IF (LNA) gain, 0-47 dB	10
-p PPM	Frequency correction in ppm	0

License

Copyright 2020-2026, Mictronics

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or any later version.