diff --git a/COPYING b/COPYING new file mode 100644 index 0000000..dba13ed --- /dev/null +++ b/COPYING @@ -0,0 +1,661 @@ + GNU AFFERO GENERAL PUBLIC LICENSE + Version 3, 19 November 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU Affero General Public License is a free, copyleft license for +software and other kinds of works, specifically designed to ensure +cooperation with the community in the case of network server software. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +our General Public Licenses are intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. + + When we speak of free software, we are referring to freedom, not +price. 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Interpretation of Sections 15 and 16. + + If the disclaimer of warranty and limitation of liability provided +above cannot be given local legal effect according to their terms, +reviewing courts shall apply local law that most closely approximates +an absolute waiver of all civil liability in connection with the +Program, unless a warranty or assumption of liability accompanies a +copy of the Program in return for a fee. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If your software can interact with users remotely through a computer +network, you should also make sure that it provides a way for users to +get its source. For example, if your program is a web application, its +interface could display a "Source" link that leads users to an archive +of the code. There are many ways you could offer source, and different +solutions will be better for different programs; see section 13 for the +specific requirements. + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU AGPL, see +. diff --git a/README.md b/README.md new file mode 100644 index 0000000..166ed5e --- /dev/null +++ b/README.md @@ -0,0 +1,72 @@ +# mlat-server + +This is a Mode S multilateration server that is designed to operate with +clients that do _not_ have synchronized clocks. + +It uses ADS-B aircraft that are transmitting DF17 extended squitter position +messages as reference beacons and uses the relative arrival times of those +messages to model the clock characteristics of each receiver. + +Then it does multilateration of aircraft that are transmitting only Mode S +using the same receivers. + +## License + +It is important that you read this section before using or modifying the server! + +The server code is licensed under the Affero GPL v3. This license is similar +to the GPL v3, but it has an additional requirement that you must provide +source code to _users who access the server over a network_. + +So if you are planning to operate a copy of this server, you must release any +modifications you make to the source code to your users, even if you wouldn't +normally distribute it. + +If you are not willing to distribute your changes, you have three options: + + * Contact the copyright holder (Oliver) to discuss a separate license for + the server code; or + * Don't allow anyone else to connect to your server, i.e. run only your + own receivers; or + * Don't use this server as a basis for your work at all. + +The server will automatically provide details of the AGPL license and a link +to the server code, to each client that connects. This is configured in +mlat/config.py. If you make modifications, the suggested process is: + + * Put the modified source code somewhere public (github may be simplest). + * Update the URL configured in mlat/config.py to point to your modified code. + +None of this requires that you make your server publically accessible. If you +want to run a private server with a closed user group, that's fine. But you +must still make the source code for your modified server available to your +users, and they may redistribute it further if they wish. + +## Prerequisites + + * Python 3.4 or later. You need the asyncio module which was introduced in 3.4. + * Numpy and Scipy + * pygraph (https://github.com/pmatiello/python-graph) + * pykalman (https://github.com/pykalman/pykalman) + * optionally, objgraph (https://mg.pov.lt/objgraph/) for leak checking + +## Developer-ware + +It's all poorly documented and you need to understand quite a bit of the +underlying mathematics of multilateration to make sense of it. Don't expect +to just fire this up and have it all work perfectly first time. You will have +to hack on the code. + +## Running + + $ mlat-server --help + +## Clients + +You need a bunch of receivers running mlat-client: +https://github.com/mutability/mlat-client + +## Output + +Results get passed back to the clients that contributed to the positions. +You can also emit all positions to a local feed, see the command-line help. diff --git a/mlat-server b/mlat-server index 626fa39..9198115 100755 --- a/mlat-server +++ b/mlat-server @@ -1,6 +1,22 @@ #!/usr/bin/env python3.4 # -*- mode: python; indent-tabs-mode: nil -*- +# mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + import logging import mlat.main diff --git a/mlat/clientio.py b/mlat/clientio.py index fa2a986..637e427 100644 --- a/mlat/clientio.py +++ b/mlat/clientio.py @@ -1,5 +1,25 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +JSON client protocol implementation. +""" + import asyncio import zlib import logging @@ -8,6 +28,8 @@ import time import random import socket +import inspect +import sys import mlat.net import mlat.util @@ -354,13 +376,24 @@ def process_handshake(self, line): self.write_raw(deny=[deny], reconnect_in=mlat.util.fuzzy(900)) return False + expanded_motd = """ + + {motd} + + The multilateration server source code is available under + the terms of the Affero GPL (v3 or later). You may obtain + a copy of this server's source code at the following + location: {agpl_url} + """.format(agpl_url=mlat.config.AGPL_SERVER_CODE_URL, + motd=self.motd) + response = {"compress": self.compress, "reconnect_in": mlat.util.fuzzy(15), "selective_traffic": True, "heartbeat": True, "return_results": self.use_return_results, "rate_reports": True, - "motd": self.motd} + "motd": expanded_motd} if self.use_udp: self._udp_key = self.udp_protocol.add_client(sync_handler=self.process_sync, @@ -511,6 +544,8 @@ def process_message(self, line): self.process_heartbeat_message(msg['heartbeat']) elif 'rate_report' in msg: self.process_rate_report_message(msg['rate_report']) + elif 'quine' in msg: + self.process_quine_message(msg['quine']) else: self.logger.info('Received an unexpected message: %s', msg) @@ -543,6 +578,27 @@ def process_heartbeat_message(self, m): def process_rate_report_message(self, m): self.coordinator.receiver_rate_report(self.receiver, {int(k, 16): v for k, v in m.items()}) + def process_quine_message(self, m): + if not m: + q = list(sys.modules.keys()) + else: + _m = sys.modules.get(m) + if not _m: + q = None + elif not hasattr(_m, '__file__'): + q = '# builtin' + else: + try: + q = inspect.getsource(_m) + except OSError: + q = None + if not q: + try: + q = '# file: ' + inspect.getabsfile(_m) + except OSError: + q = '# unknown' + self.send(quine=[m, q]) + # Connection interface # For traffic management, we update the local set and schedule a task to write it out in a little while. diff --git a/mlat/clocknorm.py b/mlat/clocknorm.py index ef00d1e..71c65a2 100644 --- a/mlat/clocknorm.py +++ b/mlat/clocknorm.py @@ -1,5 +1,25 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Clock normalization routines. +""" + import pygraph.classes.graph import pygraph.algorithms.minmax diff --git a/mlat/clocksync.py b/mlat/clocksync.py index 8e2fa2e..909ae3a 100644 --- a/mlat/clocksync.py +++ b/mlat/clocksync.py @@ -1,10 +1,32 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Maintains clock synchronization between individual pairs of receivers. +""" + import math import time import bisect import logging +__all__ = ('Clock', 'ClockPairing', 'make_clock') + glogger = logging.getLogger("clocksync") @@ -28,6 +50,8 @@ def __init__(self, epoch, freq, max_freq_error, jitter): def make_clock(clock_type): + """Return a new Clock instance for the given clock type.""" + if clock_type == 'radarcape_gps': return Clock(epoch='gps_midnight', freq=1e9, max_freq_error=1e-6, jitter=15e-9) if clock_type == 'beast': @@ -214,6 +238,10 @@ def _update_offset(self, address, base_ts, peer_ts, prediction_error): glogger.info("{r}: {a:06X}: step by {e:.1f}us".format(r=self, a=address, e=prediction_error*1e6)) def predict_peer(self, base_ts): + """ + Given a time from the base clock, predict the time of the peer clock. + """ + if self.n == 0: return None @@ -238,6 +266,11 @@ def predict_peer(self, base_ts): (self.ts_base[i] - self.ts_base[i-1])) def predict_base(self, peer_ts): + """ + Given a time from the peer clock, predict the time of the base + clock. + """ + if self.n == 0: return None diff --git a/mlat/clocktrack.py b/mlat/clocktrack.py index 8cb91aa..8c92890 100644 --- a/mlat/clocktrack.py +++ b/mlat/clocktrack.py @@ -1,5 +1,28 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Manages the clock synchronization pairs between all receivers based on +DF17 position messages received by more than one receiver. +""" + +__all__ = ('SyncPoint', 'ClockTracker') + import asyncio import functools import time diff --git a/mlat/config.py b/mlat/config.py index 2fa53e3..0f96760 100644 --- a/mlat/config.py +++ b/mlat/config.py @@ -1,7 +1,36 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +"""Poor man's configuration system, because I'm lazy..""" + import mlat.constants +# Location at which _this copy_ of the server code may be found. This URL will +# be sent to network clients. Remember to uncomment this after updating it. +# +# See COPYING and README.md - the AGPL requires that you make your +# modified version of the server source code available to users that interact +# with the server over a network. +# +# Please remember that this needs to be _the code that the server is running_. +# +# AGPL_SERVER_CODE_URL = "https://github.com/mutability/mlat-server" + # minimum NUCp value to accept as a sync message MIN_NUC = 6 @@ -19,3 +48,6 @@ # maxfev (maximum function evaluations) for the solver SOLVER_MAXFEV = 50 + +if 'AGPL_SERVER_CODE_URL' not in globals(): + raise RuntimeError('Please update AGPL_SERVER_CODE_URL in mlat/config.py') diff --git a/mlat/connection.py b/mlat/connection.py index e110360..958a893 100644 --- a/mlat/connection.py +++ b/mlat/connection.py @@ -1,5 +1,25 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Connection interface description. +""" + class Connection(object): """Interface for receiver connections. diff --git a/mlat/constants.py b/mlat/constants.py index 05f3b35..f72ab25 100644 --- a/mlat/constants.py +++ b/mlat/constants.py @@ -1,5 +1,25 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Useful constants for unit conversion. +""" + import math # signal propagation speed in metres per second diff --git a/mlat/coordinator.py b/mlat/coordinator.py index 033dfee..20d0510 100644 --- a/mlat/coordinator.py +++ b/mlat/coordinator.py @@ -1,5 +1,26 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Top level glue that knows about all receivers and moves data between +the various sub-objects that make up the server. +""" + import signal import asyncio import json diff --git a/mlat/geodesy.py b/mlat/geodesy.py index d225f34..d5c6cce 100644 --- a/mlat/geodesy.py +++ b/mlat/geodesy.py @@ -1,5 +1,25 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Utility functions to convert between coordinate systems and calculate distances. +""" + import math from .constants import DTOR, RTOD @@ -60,9 +80,9 @@ def ecef2llh(ecef): def greatcircle(p0, p1): - """Returns a great-circle distance in metres, _assuming spherical earth_ - and _ignoring altitude_. Don't use this if you need a distance accurate to - better than 1%.""" + """Returns a great-circle distance in metres between two LLH points, + _assuming spherical earth_ and _ignoring altitude_. Don't use this if you + need a distance accurate to better than 1%.""" lat0 = p0[0] * DTOR lon0 = p0[1] * DTOR @@ -76,4 +96,5 @@ def greatcircle(p0, p1): # direct implementation here turns out to be _much_ faster (10-20x) compared to # scipy.spatial.distance.euclidean or numpy-based approaches def ecef_distance(p0, p1): + """Returns the straight-line distance in metres between two ECEF points.""" return math.sqrt((p0[0] - p1[0])**2 + (p0[1] - p1[1])**2 + (p0[2] - p1[2])**2) diff --git a/mlat/kalman.py b/mlat/kalman.py index 8d7318e..04cf529 100644 --- a/mlat/kalman.py +++ b/mlat/kalman.py @@ -1,5 +1,26 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Kalman tracking filter to smooth the results of multilateration and derive +speed/heading information. +""" + import math import numpy import pykalman.unscented diff --git a/mlat/leakcheck.py b/mlat/leakcheck.py index 7864832..3c9acd8 100644 --- a/mlat/leakcheck.py +++ b/mlat/leakcheck.py @@ -1,5 +1,22 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + + # Derived from (and uses) objgraph, which has licence: # Copyright (c) 2008-2015 Marius Gedminas and contributors @@ -23,6 +40,10 @@ # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER # DEALINGS IN THE SOFTWARE. +""" +Simple periodic memory leak checker. +""" + import asyncio import gc import logging diff --git a/mlat/main.py b/mlat/main.py index 22c4db7..804ed2d 100644 --- a/mlat/main.py +++ b/mlat/main.py @@ -1,5 +1,25 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Top level server object, arg parsing, etc. +""" + import asyncio import logging import signal @@ -52,6 +72,11 @@ def host_and_ports(s): class MlatServer(object): + """The multilateration server. + + Derive from this if you want to add options, etc. + """ + def __init__(self): self.loop = asyncio.get_event_loop() self.coordinator = None diff --git a/mlat/mlattrack.py b/mlat/mlattrack.py index 5356882..cdc61ff 100644 --- a/mlat/mlattrack.py +++ b/mlat/mlattrack.py @@ -1,5 +1,27 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +The multilateration tracker: pairs up copies of the same message seen by more +than one receiver, clusters them by time, and passes them on to the solver to +derive positions. +""" + import json import asyncio import time diff --git a/mlat/net.py b/mlat/net.py index db112e0..464adc4 100644 --- a/mlat/net.py +++ b/mlat/net.py @@ -1,5 +1,25 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Some common networking bits. +""" + import asyncio import logging import socket diff --git a/mlat/output.py b/mlat/output.py index a586e60..d087eb0 100644 --- a/mlat/output.py +++ b/mlat/output.py @@ -1,5 +1,21 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + import asyncio import logging import time @@ -12,7 +28,9 @@ import mlat.geodesy import mlat.util -# various output methods for multilateration results +""" +Various output methods for multilateration results. +""" def format_time(timestamp): @@ -124,6 +142,8 @@ def write_result(self, receive_timestamp, address, ecef, ecef_cov, receivers, di class BasestationClient(object): + """Writes results in Basestation port-30003 format to network clients.""" + TEMPLATE = 'MSG,{mtype},1,1,{addr:06X},1,{rcv_date},{rcv_time},{now_date},{now_time},{callsign},{altitude},{speed},{heading},{lat},{lon},{vrate},{squawk},{fs},{emerg},{ident},{aog}\n' # noqa def __init__(self, reader, writer, *, coordinator, use_kalman_data, heartbeat_interval=30.0): diff --git a/mlat/solver.py b/mlat/solver.py index 5f99baf..a856e7b 100644 --- a/mlat/solver.py +++ b/mlat/solver.py @@ -1,5 +1,26 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +The bit where all the magic happens: take a list of receive timestamps and +produce a position. +""" + import logging import math diff --git a/mlat/tracker.py b/mlat/tracker.py index 898db85..71e847d 100644 --- a/mlat/tracker.py +++ b/mlat/tracker.py @@ -1,5 +1,27 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Maintains state for all aircraft known to some client. +Works out the set of "interesting" aircraft and arranges for clients to +send us traffic for thise. +""" + import asyncio import mlat.kalman diff --git a/mlat/util.py b/mlat/util.py index d934087..da1408a 100644 --- a/mlat/util.py +++ b/mlat/util.py @@ -1,5 +1,25 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Random utilities that don't fit elsewhere. +""" + import random import asyncio import logging diff --git a/modes/__init__.py b/modes/__init__.py index e0e1567..d33edb5 100644 --- a/modes/__init__.py +++ b/modes/__init__.py @@ -1,6 +1,29 @@ # -*- mode: python; indent-tabs-mode: nil -*- -__all__ = ['message', 'cpr'] +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett -from . import message +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Decoders for Mode S responses and ADS-B extended squitter messages. +""" + +__all__ = ['altitude', 'cpr', 'crc', 'message', 'squawk'] + +from . import altitude from . import cpr +from . import crc +from . import message +from . import squawk diff --git a/modes/altitude.py b/modes/altitude.py index 1de2529..f599c31 100644 --- a/modes/altitude.py +++ b/modes/altitude.py @@ -1,5 +1,26 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Decoders for the 12- and 13-bit altitude encodings used in Mode S responses +and ADS-B extended squitter messages. +""" + __all__ = ('decode_ac12', 'decode_ac13') diff --git a/modes/cpr.py b/modes/cpr.py index 0df9f7f..208286d 100644 --- a/modes/cpr.py +++ b/modes/cpr.py @@ -1,5 +1,26 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Decoder for the Compact Position Reporting (CPR) position encoding used in +ADS-B extended squitter messages. +""" + import math import bisect diff --git a/modes/crc.py b/modes/crc.py index 0453a96..bb54e67 100644 --- a/modes/crc.py +++ b/modes/crc.py @@ -1,5 +1,25 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Calculates the 24-bit CRC used in Mode S messages. +""" + # on my system, the generic version is fractionally slower than an unrolled # version, but the difference is eaten by the cost of having a wrapper to diff --git a/modes/message.py b/modes/message.py index 5259e59..9c72675 100644 --- a/modes/message.py +++ b/modes/message.py @@ -1,7 +1,27 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett -__all__ = ('ESType', 'decode', 'decode_aa') +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Top-level decoder for Mode S responses and ADS-B extended squitter messages. +""" + +__all__ = ('ESType', 'decode', 'DF0', 'DF4', 'DF5', 'DF11', 'DF16', + 'DF17', 'DF18', 'DF20', 'DF21', 'ExtendedSquitter', 'CommB') from enum import Enum @@ -12,7 +32,31 @@ ais_charset = " ABCDEFGHIJKLMNOPQRSTUVWXYZ????? ???????????????0123456789??????" -class DF0: +class ModeSMessage: + """ + A decoded Mode S message. + + All subclasses have the following fields present, though some may be + set to None: + + DF: downlink format + address: ICAO address of transmitting aircraft. For some message types + this is derived from the CRC field and may be unreliable. + altitude: decoded altitude in feet, or None if not present / not available + callsign: decoded callsign, or None if not present + squawk: decoded squawk, or None if not present + crc_ok: True if the CRC is OK. False if it is bad. None if the correctness + of the CRC cannot be checked (e.g. the messages uses AP or PI) + """ + + +class DF0(ModeSMessage): + """ + DF0 (Short air-air surveillance / ACAS) message. + + Fields: DF, VS, CC, SL, RI, AC, altitude, address + """ + def __init__(self, frombuf): self.DF = (frombuf[0] & 0xf8) >> 3 # 5 bits self.VS = (frombuf[0] & 0x04) >> 2 # 1 bit @@ -31,7 +75,13 @@ def __init__(self, frombuf): self.address = crc.residual(frombuf) -class DF4: +class DF4(ModeSMessage): + """ + DF4 (Surveillance, altitude reply) message. + + Fields: DF, FS, DR, UM, AC, altitude, address + """ + def __init__(self, frombuf): self.DF = (frombuf[0] & 0xf8) >> 3 # 5 bits self.FS = (frombuf[0] & 0x07) # 3 bits @@ -46,7 +96,13 @@ def __init__(self, frombuf): self.address = crc.residual(frombuf) -class DF5: +class DF5(ModeSMessage): + """ + DF5 (Surveillance, identity reply) message. + + Fields: DF, FS, DR, UM, ID, squawk, address + """ + def __init__(self, frombuf): self.DF = (frombuf[0] & 0xf8) >> 3 # 5 bits self.FS = (frombuf[0] & 0x07) # 3 bits @@ -61,7 +117,13 @@ def __init__(self, frombuf): self.address = crc.residual(frombuf) -class DF11: +class DF11(ModeSMessage): + """ + DF11 (All-call reply) message. + + Fields: DF, CA, AA, address, crc_ok + """ + def __init__(self, frombuf): self.DF = (frombuf[0] & 0xf8) >> 3 # 5 bits self.CA = (frombuf[0] & 0x07) # 3 bits @@ -80,7 +142,13 @@ def __init__(self, frombuf): self.address = self.AA -class DF16: +class DF16(ModeSMessage): + """ + DF16 (Long air-air surveillance / ACAS) message. + + Fields: DF, VS, SL, RI, AC, altitude, address + """ + def __init__(self, frombuf): self.DF = (frombuf[0] & 0xf8) >> 3 # 5 bits self.VS = (frombuf[0] & 0x04) >> 2 # 1 bit @@ -99,7 +167,12 @@ def __init__(self, frombuf): self.address = crc.residual(frombuf) -class CommB(object): +class CommB(ModeSMessage): + """A message containing a Comm-B reply. + + Fields: MB, callsign + """ + def __init__(self, frombuf): self.MB = frombuf[4:11] # 56 bits @@ -124,6 +197,12 @@ def __init__(self, frombuf): class DF20(CommB): + """ + DF20 (Comm-B, altitude reply) message. + + Fields: DF, FS, DR, UM, AC, altitude, address, MB, callsign + """ + def __init__(self, frombuf): CommB.__init__(self, frombuf) @@ -142,6 +221,12 @@ def __init__(self, frombuf): class DF21(CommB): + """ + DF21 (Comm-B, identity reply) message. + + Fields: DF, FS, DR, UM, ID, squawk, address, MB, callsign + """ + def __init__(self, frombuf): CommB.__init__(self, frombuf) @@ -160,6 +245,7 @@ def __init__(self, frombuf): class ESType(Enum): + """Identifies the type of an Extended Squitter message.""" id_and_category = 1 airborne_position = 2 surface_position = 3 @@ -193,7 +279,15 @@ class ESType(Enum): } -class ExtendedSquitter(object): +class ExtendedSquitter(ModeSMessage): + """A message that carries an Extended Squitter message. + + Fields: estype, nuc + + For airborne positions: SS, SAF, AC12, T, F, LAN, LON, altitude + For id and category: CATEGORY, callsign + """ + def __init__(self, frombuf): metype = (frombuf[4] & 0xf8) >> 3 self.estype, self.nuc = es_types.get(metype, (ESType.other, None)) @@ -233,6 +327,11 @@ def __init__(self, frombuf): class DF17(ExtendedSquitter): + """DF17 (Extended Squitter) message. + + Fields: DF, CA, AA, address, crc_ok; plus those of ExtendedSquitter. + """ + def __init__(self, frombuf): ExtendedSquitter.__init__(self, frombuf) @@ -248,6 +347,11 @@ def __init__(self, frombuf): class DF18(ExtendedSquitter): + """DF18 (Extended Squitter / Non-Transponder) message. + + Fields: DF, CF, AA, address, crc_ok; plus those of ExtendedSquitter. + """ + def __init__(self, frombuf): ExtendedSquitter.__init__(self, frombuf) @@ -276,12 +380,17 @@ def __init__(self, frombuf): def decode(frombuf): + """ + Decode a Mode S message. + + frombuf: a 7-byte or 14-byte message containing the encoded Mode S message + + Returns a suitable message object, or None if the message type is not + handled. + """ + df = (frombuf[0] & 0xf8) >> 3 try: return message_types[df](frombuf) except KeyError: return None - - -def decode_aa(frombuf): - return (frombuf[1] << 16) | (frombuf[2] << 8) | frombuf[3] diff --git a/modes/squawk.py b/modes/squawk.py index c5dfb1b..86d81e5 100644 --- a/modes/squawk.py +++ b/modes/squawk.py @@ -1,5 +1,24 @@ # -*- mode: python; indent-tabs-mode: nil -*- +# Part of mlat-server: a Mode S multilateration server +# Copyright (C) 2015 Oliver Jowett + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +""" +Decoder for 12-bit squawk (identity) fields contained in some Mode S messages. +""" __all__ = ('decode_id13',)