PyModeS is a Python library designed to decode Mode-S (including ADS-B) messages. It can be imported to your python project or used as a standalone tool to view and save live traffic data.
This is a project created by Junzi Sun, who works at TU Delft, Aerospace Engineering Faculty, CNS/ATM research group. It is supported by many contributors from different institutions.
pyModeS supports the decoding of following types of messages:
- DF4 / DF20: Altitude code
- DF5 / DF21: Identity code (squawk code)
- DF17 / DF18: Automatic Dependent Surveillance-Broadcast (ADS-B)
- TC=1-4 / BDS 0,8: Aircraft identification and category
- TC=5-8 / BDS 0,6: Surface position
- TC=9-18 / BDS 0,5: Airborne position
- TC=19 / BDS 0,9: Airborne velocity
- TC=28 / BDS 6,1: Airborne status [to be implemented]
- TC=29 / BDS 6,2: Target state and status information [to be implemented]
- TC=31 / BDS 6,5: Aircraft operational status [to be implemented]
- DF20 / DF21: Mode-S Comm-B messages
- BDS 1,0: Data link capability report
- BDS 1,7: Common usage GICB capability report
- BDS 2,0: Aircraft identification
- BDS 3,0: ACAS active resolution advisory
- BDS 4,0: Selected vertical intention
- BDS 4,4: Meteorological routine air report (experimental)
- BDS 4,5: Meteorological hazard report (experimental)
- BDS 5,0: Track and turn report
- BDS 6,0: Heading and speed report
If you find this project useful for your research, please considering cite this tool as:
@article{sun2019pymodes, author={J. {Sun} and H. {V\^u} and J. {Ellerbroek} and J. M. {Hoekstra}}, journal={IEEE Transactions on Intelligent Transportation Systems}, title={pyModeS: Decoding Mode-S Surveillance Data for Open Air Transportation Research}, year={2019}, doi={10.1109/TITS.2019.2914770}, ISSN={1524-9050}, }
Check out and contribute to this open-source project at: https://github.com/junzis/pyModeS
Detailed manual on Mode-S decoding is published at: https://mode-s.org/decode
The API documentation of pyModeS is at: https://mode-s.org/api
Installation examples:
# stable version pip install pyModeS # conda (compiled) version conda install -c conda-forge pymodes # development version pip install git+https://github.com/junzis/pyModeS
Dependencies numpy
, and pyzmq
are installed automatically during previous installations processes.
If you need to connect pyModeS to a RTL-SDR receiver, pyrtlsdr
need to be installed manually:
pip install pyrtlsdr
If you want to make use of the (faster) c module, install pyModeS
as follows:
# conda (compiled) version conda install -c conda-forge pymodes # stable version pip install pyModeS # development version git clone https://github.com/junzis/pyModeS cd pyModeS poetry install -E rtlsdr
General usage:
$ modeslive [-h] --source SOURCE [--connect SERVER PORT DATAYPE] [--latlon LAT LON] [--show-uncertainty] [--dumpto DUMPTO] arguments: -h, --help show this help message and exit --source SOURCE Choose data source, "rtlsdr" or "net" --connect SERVER PORT DATATYPE Define server, port and data type. Supported data types are: ['raw', 'beast', 'skysense'] --latlon LAT LON Receiver latitude and longitude, needed for the surface position, default none --show-uncertainty Display uncertainty values, default off --dumpto DUMPTO Folder to dump decoded output, default none
If you have an RTL-SDR receiver connected to your computer, you can use the rtlsdr
source switch (require pyrtlsdr
package), with command:
$ modeslive --source rtlsdr
If you want to connect to a TCP server that broadcast raw data. use can use net
source switch, for example:
$ modeslive --source net --connect localhost 30002 raw $ modeslive --source net --connect 127.0.0.1 30005 beast
Example screenshot:
import pyModeS as pms
pms.df(msg) # Downlink Format
pms.icao(msg) # Infer the ICAO address from the message
pms.crc(msg, encode=False) # Perform CRC or generate parity bit
pms.hex2bin(str) # Convert hexadecimal string to binary string
pms.bin2int(str) # Convert binary string to integer
pms.hex2int(str) # Convert hexadecimal string to integer
pms.gray2int(str) # Convert grey code to integer
pms.adsb.icao(msg)
pms.adsb.typecode(msg)
# Typecode 1-4
pms.adsb.callsign(msg)
# Typecode 5-8 (surface), 9-18 (airborne, barometric height), and 20-22 (airborne, GNSS height)
pms.adsb.position(msg_even, msg_odd, t_even, t_odd, lat_ref=None, lon_ref=None)
pms.adsb.airborne_position(msg_even, msg_odd, t_even, t_odd)
pms.adsb.surface_position(msg_even, msg_odd, t_even, t_odd, lat_ref, lon_ref)
pms.adsb.surface_velocity(msg)
pms.adsb.position_with_ref(msg, lat_ref, lon_ref)
pms.adsb.airborne_position_with_ref(msg, lat_ref, lon_ref)
pms.adsb.surface_position_with_ref(msg, lat_ref, lon_ref)
pms.adsb.altitude(msg)
# Typecode: 19
pms.adsb.velocity(msg) # Handles both surface & airborne messages
pms.adsb.speed_heading(msg) # Handles both surface & airborne messages
pms.adsb.airborne_velocity(msg)
Note: When you have a fix position of the aircraft, it is convenient to use position_with_ref() method to decode with only one position message (either odd or even). This works with both airborne and surface position messages. But the reference position shall be within 180NM (airborne) or 45NM (surface) of the true position.
pms.common.altcode(msg) # Downlink format must be 4 or 20
pms.common.idcode(msg) # Downlink format must be 5 or 21
pms.icao(msg) # Infer the ICAO address from the message
pms.bds.infer(msg) # Infer the Modes-S BDS register
# Check if BDS is 5,0 or 6,0, give reference speed, track, altitude (from ADS-B)
pms.bds.is50or60(msg, spd_ref, trk_ref, alt_ref)
# Check each BDS explicitly
pms.bds.bds10.is10(msg)
pms.bds.bds17.is17(msg)
pms.bds.bds20.is20(msg)
pms.bds.bds30.is30(msg)
pms.bds.bds40.is40(msg)
pms.bds.bds44.is44(msg)
pms.bds.bds50.is50(msg)
pms.bds.bds60.is60(msg)
pms.commb.ovc10(msg) # Overlay capability, BDS 1,0
pms.commb.cap17(msg) # GICB capability, BDS 1,7
pms.commb.cs20(msg) # Callsign, BDS 2,0
# BDS 4,0
pms.commb.selalt40mcp(msg) # MCP/FCU selected altitude (ft)
pms.commb.selalt40fms(msg) # FMS selected altitude (ft)
pms.commb.p40baro(msg) # Barometric pressure (mb)
# BDS 5,0
pms.commb.roll50(msg) # Roll angle (deg)
pms.commb.trk50(msg) # True track angle (deg)
pms.commb.gs50(msg) # Ground speed (kt)
pms.commb.rtrk50(msg) # Track angle rate (deg/sec)
pms.commb.tas50(msg) # True airspeed (kt)
# BDS 6,0
pms.commb.hdg60(msg) # Magnetic heading (deg)
pms.commb.ias60(msg) # Indicated airspeed (kt)
pms.commb.mach60(msg) # Mach number (-)
pms.commb.vr60baro(msg) # Barometric altitude rate (ft/min)
pms.commb.vr60ins(msg) # Inertial vertical speed (ft/min)
To identify BDS 4,4 and 4,5 codes, you must set mrar
argument to True
in the infer()
function:
pms.bds.infer(msg. mrar=True)
Once the correct MRAR and MHR messages are identified, decode them as follows:
# BDS 4,4
pms.commb.wind44(msg) # Wind speed (kt) and direction (true) (deg)
pms.commb.temp44(msg) # Static air temperature (C)
pms.commb.p44(msg) # Average static pressure (hPa)
pms.commb.hum44(msg) # Humidity (%)
# BDS 4,5
pms.commb.turb45(msg) # Turbulence level (0-3)
pms.commb.ws45(msg) # Wind shear level (0-3)
pms.commb.mb45(msg) # Microburst level (0-3)
pms.commb.ic45(msg) # Icing level (0-3)
pms.commb.wv45(msg) # Wake vortex level (0-3)
pms.commb.temp45(msg) # Static air temperature (C)
pms.commb.p45(msg) # Average static pressure (hPa)
pms.commb.rh45(msg) # Radio height (ft)
The TCP client module from pyModeS can be re-used to stream and process Mode-S data as you like. You need to re-implement the handle_messages()
function from the TcpClient
class to write your own logic to handle the messages.
Here is an example:
import pyModeS as pms
from pyModeS.extra.tcpclient import TcpClient
# define your custom class by extending the TcpClient
# - implement your handle_messages() methods
class ADSBClient(TcpClient):
def __init__(self, host, port, rawtype):
super(ADSBClient, self).__init__(host, port, rawtype)
def handle_messages(self, messages):
for msg, ts in messages:
if len(msg) != 28: # wrong data length
continue
df = pms.df(msg)
if df != 17: # not ADSB
continue
if pms.crc(msg) !=0: # CRC fail
continue
icao = pms.adsb.icao(msg)
tc = pms.adsb.typecode(msg)
# TODO: write you magic code here
print(ts, icao, tc, msg)
# run new client, change the host, port, and rawtype if needed
client = ADSBClient(host='127.0.0.1', port=30005, rawtype='beast')
client.run()
To perform unit tests, pytest
must be install first.
Build Cython extensions
$ make ext
Run unit tests
$ make test
Clean build files
$ make clean