Package: pymodes
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 atTU Delft,Aerospace Engineering Faculty,CNS/ATM research group. It is supported by manycontributorsfrom different institutions.IntroductionpyModeS supports the decoding of following types of messages:DF4 / DF20: Altitude codeDF5 / DF21: Identity code (squawk code)DF17 / DF18: Automatic Dependent Surveillance-Broadcast (ADS-B)TC=1-4  / BDS 0,8: Aircraft identification and categoryTC=5-8  / BDS 0,6: Surface positionTC=9-18 / BDS 0,5: Airborne positionTC=19   / BDS 0,9: Airborne velocityTC=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 messagesBDS 1,0: Data link capability reportBDS 1,7: Common usage GICB capability reportBDS 2,0: Aircraft identificationBDS 3,0: ACAS active resolution advisoryBDS 4,0: Selected vertical intentionBDS 4,4: Meteorological routine air report (experimental)BDS 4,5: Meteorological hazard report (experimental)BDS 5,0: Track and turn reportBDS 6,0: Heading and speed reportIf 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},
}ResourcesCheck out and contribute to this open-source project at:https://github.com/junzis/pyModeSDetailed manual on Mode-S decoding is published at:https://mode-s.org/decodeThe API documentation of pyModeS is at:https://mode-s.org/apiBasic installationInstallation examples:# stable version
pip install pyModeS

# conda (compiled) version
conda install -c conda-forge pymodes

# development version
pip install git+https://github.com/junzis/pyModeSDependenciesnumpy, andpyzmqare installed automatically during previous installations processes.If you need to connect pyModeS to a RTL-SDR receiver,pyrtlsdrneed to be installed manually:pip install pyrtlsdrAdvanced installation (using c modules)If you want to make use of the (faster) c module, installpyModeSas 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 rtlsdrView live traffic (modeslive)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 noneLive with RTL-SDRIf you have an RTL-SDR receiver connected to your computer, you can use thertlsdrsource switch (requirepyrtlsdrpackage), with command:$ modeslive --source rtlsdrLive with network dataIf you want to connect to a TCP server that broadcast raw data. use can usenetsource switch, for example:$ modeslive --source net --connect localhost 30002 raw
$ modeslive --source net --connect 127.0.0.1 30005 beastExample screenshot:Use the libraryimportpyModeSaspmsCommon functionspms.df(msg)# Downlink Formatpms.icao(msg)# Infer the ICAO address from the messagepms.crc(msg,encode=False)# Perform CRC or generate parity bitpms.hex2bin(str)# Convert hexadecimal string to binary stringpms.bin2int(str)# Convert binary string to integerpms.hex2int(str)# Convert hexadecimal string to integerpms.gray2int(str)# Convert grey code to integerCore functions for ADS-B decodingpms.adsb.icao(msg)pms.adsb.typecode(msg)# Typecode 1-4pms.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: 19pms.adsb.velocity(msg)# Handles both surface & airborne messagespms.adsb.speed_heading(msg)# Handles both surface & airborne messagespms.adsb.airborne_velocity(msg)Note: When you have a fix position of the aircraft, it is convenient to useposition_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.Decode altitude replies in DF4 / DF20pms.common.altcode(msg)# Downlink format must be 4 or 20Decode identity replies in DF5 / DF21pms.common.idcode(msg)# Downlink format must be 5 or 21Common Mode-S functionspms.icao(msg)# Infer the ICAO address from the messagepms.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 explicitlypms.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)Mode-S Elementary Surveillance (ELS)pms.commb.ovc10(msg)# Overlay capability, BDS 1,0pms.commb.cap17(msg)# GICB capability, BDS 1,7pms.commb.cs20(msg)# Callsign, BDS 2,0Mode-S Enhanced Surveillance (EHS)# BDS 4,0pms.commb.selalt40mcp(msg)# MCP/FCU selected altitude (ft)pms.commb.selalt40fms(msg)# FMS selected altitude (ft)pms.commb.p40baro(msg)# Barometric pressure (mb)# BDS 5,0pms.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 6,0pms.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)Meteorological reports [Experimental]To identify BDS 4,4 and 4,5 codes, you must setmrarargument toTruein theinfer()function:pms.bds.infer(msg.mrar=True)Once the correct MRAR and MHR messages are identified, decode them as follows:Meteorological routine air report (MRAR)# BDS 4,4pms.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 (%)Meteorological hazard air report (MHR)# BDS 4,5pms.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)Customize the streaming moduleThe TCP client module from pyModeS can be re-used to stream and process Mode-S data as you like. You need to re-implement thehandle_messages()function from theTcpClientclass to write your own logic to handle the messages.Here is an example:importpyModeSaspmsfrompyModeS.extra.tcpclientimportTcpClient# define your custom class by extending the TcpClient#   - implement your handle_messages() methodsclassADSBClient(TcpClient):def__init__(self,host,port,rawtype):super(ADSBClient,self).__init__(host,port,rawtype)defhandle_messages(self,messages):formsg,tsinmessages:iflen(msg)!=28:# wrong data lengthcontinuedf=pms.df(msg)ifdf!=17:# not ADSBcontinueifpms.crc(msg)!=0:# CRC failcontinueicao=pms.adsb.icao(msg)tc=pms.adsb.typecode(msg)# TODO: write you magic code hereprint(ts,icao,tc,msg)# run new client, change the host, port, and rawtype if neededclient=ADSBClient(host='127.0.0.1',port=30005,rawtype='beast')client.run()Unit testTo perform unit tests,pytestmust be install first.Build Cython extensions$ make extRun unit tests$ make testClean build files$ make clean