initial commit for v2.0

2017-12-20 17:00:02 +01:00
parent 2b1f2a5878
commit d13e1bd12e
15 changed files with 756 additions and 9 deletions
@@ -0,0 +1,992 @@
+# Copyright (C) 2016 Junzi Sun (TU Delft)
+
+# 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
+# (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 General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""
+A python package for decoding ModeS (DF20, DF21) messages.
+"""
+
+from __future__ import absolute_import, print_function, division
+from . import util, modes_common
+
+def icao(msg):
+    return modes_common.icao(msg)
+
+def data(msg):
+    """Return the data frame in the message, bytes 9 to 22"""
+    return msg[8:22]
+
+def isnull(msg):
+    """check if the data bits are all zeros
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        bool: True or False
+    """
+    d = util.hex2bin(data(msg))
+
+    if util.bin2int(d) > 0:
+        return False
+    else:
+        return True
+
+def checkbits(data, sb, msb, lsb):
+    """Check if the status bit and field bits are consistency. This Function
+    is used for checking BDS code versions.
+    """
+
+    # status bit, most significant bit, least significant bit
+    status = int(data[sb-1])
+    value = util.bin2int(data[msb-1:lsb])
+
+    if not status:
+        if value != 0:
+            return False
+
+    return True
+
+# ------------------------------------------
+# Common functions
+# ------------------------------------------
+
+def df20alt(msg):
+    """Computes the altitude from DF20 message, bit 20-32
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        int: altitude in ft
+    """
+
+    if util.df(msg) != 20:
+        raise RuntimeError("Message must be Downlink Format 20.")
+
+    return modes_common.altcode(msg)
+
+
+def df21id(msg):
+    """Computes identity (squawk code) from DF21, bit 20-32
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        string: squawk code
+    """
+
+    if util.df(msg) != 21:
+        raise RuntimeError("Message must be Downlink Format 21.")
+
+    return modes_common.idcode(msg)
+
+# ------------------------------------------
+# BDS 1,7
+# Common usage GICB capability report
+# ------------------------------------------
+
+def isBDS17(msg):
+    """Check if a message is likely to be BDS code 1,7
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        bool: True or False
+    """
+
+    if isnull(msg):
+        return False
+
+    d = util.hex2bin(data(msg))
+
+    result = True
+
+    if util.bin2int(d[28:56]) != 0:
+        result &= False
+
+    caps = cap17(msg)
+
+    # basic BDS codes for ADS-B shall be supported
+    #   assuming ADS-B out is installed (2017EU/2020US mandate)
+    if not set(['BDS05', 'BDS06', 'BDS09', 'BDS20']).issubset(caps):
+        result &= False
+
+    return result
+
+def cap17(msg):
+    """Extract capacities from BDS 1,7 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        list: list of suport BDS codes
+    """
+    allbds = ['05', '06', '07', '08', '09', '0A', '20', '21', '40', '41',
+              '42', '43', '44', '45', '48', '50', '51', '52', '53', '54',
+              '55', '56', '5F', '60', 'NA', 'NA', 'E1', 'E2']
+
+    d = util.hex2bin(data(msg))
+    idx = [i for i, v in enumerate(d[:28]) if v=='1']
+    capacity = ['BDS'+allbds[i] for i in idx if allbds[i] is not 'NA']
+
+    return capacity
+
+# ------------------------------------------
+# BDS 2,0
+# Aircraft identification
+# ------------------------------------------
+
+def isBDS20(msg):
+    """Check if a message is likely to be BDS code 2,0
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        bool: True or False
+    """
+
+    if isnull(msg):
+        return False
+
+    # status bit 1, 14, and 27
+    d = util.hex2bin(data(msg))
+
+    result = True
+
+    if util.bin2int(d[0:4]) != 2 or util.bin2int(d[4:8]) != 0:
+        result &= False
+
+    cs = callsign(msg)
+
+    if '#' in cs:
+        result &= False
+
+    return result
+
+
+def callsign(msg):
+    """Aircraft callsign
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS40) string
+
+    Returns:
+        string: callsign, max. 8 chars
+    """
+    chars = '#ABCDEFGHIJKLMNOPQRSTUVWXYZ#####_###############0123456789######'
+
+    d = util.hex2bin(data(msg))
+
+    cs = ''
+    cs += chars[util.bin2int(d[8:14])]
+    cs += chars[util.bin2int(d[14:20])]
+    cs += chars[util.bin2int(d[20:26])]
+    cs += chars[util.bin2int(d[26:32])]
+    cs += chars[util.bin2int(d[32:38])]
+    cs += chars[util.bin2int(d[38:44])]
+    cs += chars[util.bin2int(d[44:50])]
+    cs += chars[util.bin2int(d[50:56])]
+
+    return cs
+
+
+# ------------------------------------------
+# BDS 4,0
+# Selected vertical intention
+# ------------------------------------------
+
+def isBDS40(msg):
+    """Check if a message is likely to be BDS code 4,0
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        bool: True or False
+    """
+
+    if isnull(msg):
+        return False
+
+    # status bit 1, 14, and 27
+    d = util.hex2bin(data(msg))
+
+    result = True
+
+    result = result & checkbits(d, 1, 2, 13) \
+        & checkbits(d, 14, 15, 26) & checkbits(d, 27, 28, 39)
+
+    # bits 40-47 and 52-53 shall all be zero
+    if util.bin2int(d[39:47]) != 0:
+        result &= False
+
+    if util.bin2int(d[51:53]) != 0:
+        result &= False
+
+    return result
+
+
+def alt40mcp(msg):
+    """Selected altitude, MCP/FCU
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS40) string
+
+    Returns:
+        int: altitude in feet
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[0] == '0':
+        return None
+
+    alt = util.bin2int(d[1:13]) * 16    # ft
+    return alt
+
+
+def alt40fms(msg):
+    """Selected altitude, FMS
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS40) string
+
+    Returns:
+        int: altitude in feet
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[13] == '0':
+        return None
+
+    alt = util.bin2int(d[14:26]) * 16    # ft
+    return alt
+
+
+def p40baro(msg):
+    """Barometric pressure setting
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS40) string
+
+    Returns:
+        float: pressure in millibar
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[26] == '0':
+        return None
+
+    p = util.bin2int(d[27:39]) * 0.1 + 800    # millibar
+    return p
+
+
+# ------------------------------------------
+# BDS 4,4
+# Meteorological routine air report
+# ------------------------------------------
+
+def isBDS44(msg, rev=False):
+    """Check if a message is likely to be BDS code 4,4
+    Meteorological routine air report
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+        rev (bool): using revised version
+
+    Returns:
+        bool: True or False
+    """
+
+    if isnull(msg):
+        return False
+
+    d = util.hex2bin(data(msg))
+
+    result = True
+
+    if not rev:
+        # status bit 5, 35, 47, 50
+        result = result & checkbits(d, 5, 6, 23) \
+            & checkbits(d, 35, 36, 46) & checkbits(d, 47, 48, 49) \
+            & checkbits(d, 50, 51, 56)
+        # Bits 1-4 indicate source, values > 4 reserved and should not occur
+        if util.bin2int(d[0:4]) > 4:
+            result &= False
+    else:
+        # status bit 5, 15, 24, 36, 49
+        result = result & checkbits(d, 5, 6, 14) \
+            & checkbits(d, 15, 16, 23) & checkbits(d, 24, 25, 35) \
+            & checkbits(d, 36, 37, 47) & checkbits(d, 49, 50, 56)
+        # Bits 1-4 are reserved and should be zero
+        if util.bin2int(d[0:4]) != 0:
+            result &= False
+        
+    if not result:
+        return False
+
+    vw = wind44(msg, rev=rev)
+    if vw is not None and vw[0] > 250:
+        result &= False
+
+    if temp44(msg):
+        if temp44(msg) > 60 or temp44(msg) < -80:
+            result &= False
+    elif temp44(msg) == 0:
+        result &= False
+
+    return result
+
+
+def wind44(msg, rev=False):
+    """reported wind speed and direction
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS44) string
+        rev (bool): using revised version
+
+    Returns:
+        (int, float): speed (kt), direction (degree)
+    """
+    d = util.hex2bin(data(msg))
+
+    if not rev:
+        status = int(d[4])
+        if not status:
+            return None
+
+        speed = util.bin2int(d[5:14])   # knots
+        direction = util.bin2int(d[14:23]) * 180.0 / 256.0  # degree
+
+    else:
+        spd_status = int(d[4])
+        dir_status = int(d[14])
+
+        if (not spd_status) or (not dir_status):
+            return None
+
+        speed = util.bin2int(d[5:14])   # knots
+        direction = util.bin2int(d[15:23]) * 180.0 / 128.0  # degree
+
+    return round(speed, 0), round(direction, 1)
+
+
+def temp44(msg, rev=False):
+    """reported air temperature
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS44) string
+        rev (bool): using revised version
+
+    Returns:
+        float: tmeperature in Celsius degree
+    """
+    d = util.hex2bin(data(msg))
+
+    if not rev:
+        # if d[22] == '0':
+        #     return None
+
+        sign = int(d[23])
+        value = util.bin2int(d[24:34])
+
+        if sign:
+            value = value - 1024
+
+        temp = value * 0.125   # celsius
+        temp = round(temp, 1)
+    else:
+        # if d[23] == '0':
+        #     return None
+
+        sign = int(d[24])
+        value = util.bin2int(d[25:35])
+
+        if sign:
+            value = value - 1024
+
+        temp = value * 0.125   # celsius
+        temp = round(temp, 1)
+
+    return -1*temp if sign else temp
+
+
+def p44(msg, rev=False):
+    """reported average static pressure
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS44) string
+        rev (bool): using revised version
+
+    Returns:
+        int: static pressure in hPa
+    """
+    d = util.hex2bin(data(msg))
+
+    if not rev:
+        if d[34] == '0':
+            return None
+
+        p = util.bin2int(d[35:46])    # hPa
+
+    else:
+        if d[35] == '0':
+            return None
+
+        p = util.bin2int(d[36:47])    # hPa
+
+    return p
+
+
+def hum44(msg, rev=False):
+    """reported humidity
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS44) string
+        rev (bool): using revised version
+
+    Returns:
+        float: percentage of humidity, [0 - 100] %
+    """
+    d = util.hex2bin(data(msg))
+
+    if not rev:
+        if d[49] == '0':
+            return None
+
+        hm = util.bin2int(d[50:56]) * 100.0 / 64    # %
+
+    else:
+        if d[48] == '0':
+            return None
+
+        hm = util.bin2int(d[49:56])    # %
+
+    return round(hm, 1)
+
+
+# ------------------------------------------
+# BDS 5,0
+# Track and turn report
+# ------------------------------------------
+
+def isBDS50(msg):
+    """Check if a message is likely to be BDS code 5,0
+    (Track and turn report)
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        bool: True or False
+    """
+
+    if isnull(msg):
+        return False
+
+    # status bit 1, 12, 24, 35, 46
+    d = util.hex2bin(data(msg))
+
+    result = True
+
+    result = result & checkbits(d, 1, 3, 11) & checkbits(d, 12, 13, 23) \
+        & checkbits(d, 24, 25, 34) & checkbits(d, 35, 36, 45) \
+        & checkbits(d, 46, 47, 56)
+
+    if not result:
+        return False
+
+    if d[2:11] == "000000000":
+        result &= True
+    else:
+        roll = abs(roll50(msg))
+        if roll and roll > 60:
+            result &= False
+
+    gs = gs50(msg)
+    if gs is not None and gs > 600:
+        result &= False
+
+    tas = tas50(msg)
+    if tas is not None and tas > 500:
+        result &= False
+
+    if (gs is not None) and (tas is not None) and (abs(tas - gs) > 200):
+        result &= False
+
+    return result
+
+
+def roll50(msg):
+    """Roll angle, BDS 5,0 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS50) string
+
+    Returns:
+        float: angle in degrees,
+               negative->left wing down, positive->right wing down
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[0] == '0':
+        return None
+
+    sign = int(d[1])    # 1 -> left wing down
+    value = util.bin2int(d[2:11])
+
+    if sign:
+        value = value - 512
+
+    angle = value * 45.0 / 256.0    # degree
+    return round(angle, 1)
+
+
+def trk50(msg):
+    """True track angle, BDS 5,0 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS50) string
+
+    Returns:
+        float: angle in degrees to true north (from 0 to 360)
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[11] == '0':
+        return None
+
+    sign = int(d[12])   # 1 -> west
+    value = util.bin2int(d[13:23])
+
+    if sign:
+        value = value - 1024
+
+    trk = value * 90.0 / 512.0
+
+    # convert from [-180, 180] to [0, 360]
+    if trk < 0:
+        trk = 360 + trk
+
+    return round(trk, 1)
+
+
+def gs50(msg):
+    """Ground speed, BDS 5,0 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS50) string
+
+    Returns:
+        int: ground speed in knots
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[23] == '0':
+        return None
+
+    spd = util.bin2int(d[24:34]) * 2    # kts
+    return spd
+
+
+def rtrk50(msg):
+    """Track angle rate, BDS 5,0 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS50) string
+
+    Returns:
+        float: angle rate in degrees/second
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[34] == '0':
+        return None
+
+    if d[36:45] == "111111111":
+        return None
+
+    sign = int(d[35])    # 1 -> minus
+    value = util.bin2int(d[36:45])
+    if sign:
+        value = value - 512
+
+    angle = value * 8.0 / 256.0    # degree / sec
+    return round(angle, 3)
+
+
+def tas50(msg):
+    """Aircraft true airspeed, BDS 5,0 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS50) string
+
+    Returns:
+        int: true airspeed in knots
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[45] == '0':
+        return None
+
+    tas = util.bin2int(d[46:56]) * 2   # kts
+    return tas
+
+
+# ------------------------------------------
+# BDS 5,3
+# Air-referenced state vector
+# ------------------------------------------
+
+def isBDS53(msg):
+    """Check if a message is likely to be BDS code 5,3
+    (Air-referenced state vector)
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        bool: True or False
+    """
+
+    if isnull(msg):
+        return False
+
+    # status bit 1, 13, 24, 34, 47
+    d = util.hex2bin(data(msg))
+
+    result = True
+
+    result = result & checkbits(d, 1, 3, 12) & checkbits(d, 13, 14, 23) \
+        & checkbits(d, 24, 25, 33) & checkbits(d, 34, 35, 46) \
+        & checkbits(d, 47, 49, 56)
+
+    if not result:
+        return False
+
+    ias = ias53(msg)
+    if ias is not None and ias > 500:
+        result &= False
+
+    mach = mach53(msg)
+    if mach is not None and mach > 1:
+        result &= False
+
+    tas = tas53(msg)
+    if tas is not None and tas > 500:
+        result &= False
+
+    vr = vr53(msg)
+    if vr is not None and abs(vr) > 8000:
+        result &= False
+
+    return result
+
+
+def hdg53(msg):
+    """Magnetic heading, BDS 5,3 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS53) string
+
+    Returns:
+        float: angle in degrees to true north (from 0 to 360)
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[0] == '0':
+        return None
+
+    sign = int(d[1])    # 1 -> west
+    value = util.bin2int(d[2:12])
+
+    if sign:
+        value = value - 1024
+
+    hdg = value * 90.0 / 512.0   # degree
+
+    # convert from [-180, 180] to [0, 360]
+    if hdg < 0:
+        hdg = 360 + hdg
+
+    return round(hdg, 1)
+
+
+def ias53(msg):
+    """Indicated airspeed, DBS 5,3 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message
+
+    Returns:
+        int: indicated arispeed in knots
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[12] == '0':
+        return None
+
+    ias = util.bin2int(d[13:23])    # knots
+    return ias
+
+
+def mach53(msg):
+    """MACH number, DBS 5,3 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message
+
+    Returns:
+        float: MACH number
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[23] == '0':
+        return None
+
+    mach = util.bin2int(d[24:33]) * 0.008
+    return round(mach, 3)
+
+
+def tas53(msg):
+    """Aircraft true airspeed, BDS 5,3 message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message
+
+    Returns:
+        float: true airspeed in knots
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[33] == '0':
+        return None
+
+    tas = util.bin2int(d[34:46]) * 0.5   # kts
+    return round(tas, 1)
+
+def vr53(msg):
+    """Vertical rate
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS60) string
+
+    Returns:
+        int: vertical rate in feet/minutes
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[46] == '0':
+        return None
+
+    sign = d[47]    # 1 -> minus
+    value = util.bin2int(d[48:56])
+
+    if sign:
+        value = value - 256
+    roc = value * 64     # feet/min
+    return roc
+
+
+# ------------------------------------------
+# BDS 6,0
+# ------------------------------------------
+
+def isBDS60(msg):
+    """Check if a message is likely to be BDS code 6,0
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        bool: True or False
+    """
+
+    if isnull(msg):
+        return False
+
+    # status bit 1, 13, 24, 35, 46
+    d = util.hex2bin(data(msg))
+
+    result = True
+
+    result = result & checkbits(d, 1, 2, 12) & checkbits(d, 13, 14, 23) \
+        & checkbits(d, 24, 25, 34) & checkbits(d, 35, 36, 45) \
+        & checkbits(d, 46, 47, 56)
+
+    if not result:
+        return False
+
+    ias = ias60(msg)
+    if ias is not None and ias > 500:
+        result &= False
+
+    mach = mach60(msg)
+    if mach is not None and mach > 1:
+        result &= False
+
+    # leave out the check from vertical rates,
+    #   due to very noisy measurement
+
+    return result
+
+
+def hdg60(msg):
+    """Megnetic heading of aircraft
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS60) string
+
+    Returns:
+        float: heading in degrees to megnetic north (from 0 to 360)
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[0] == '0':
+        return None
+
+    sign = int(d[1])    # 1 -> west
+    value = util.bin2int(d[2:12])
+
+    if sign:
+        value = value - 1024
+
+    hdg = value * 90 / 512.0  # degree
+
+    # convert from [-180, 180] to [0, 360]
+    if hdg < 0:
+        hdg = 360 + hdg
+
+    return round(hdg, 1)
+
+
+def ias60(msg):
+    """Indicated airspeed
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS60) string
+
+    Returns:
+        int: indicated airspeed in knots
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[12] == '0':
+        return None
+
+    ias = util.bin2int(d[13:23])    # kts
+    return ias
+
+
+def mach60(msg):
+    """Aircraft MACH number
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS60) string
+
+    Returns:
+        float: MACH number
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[23] == '0':
+        return None
+
+    mach = util.bin2int(d[24:34]) * 2.048 / 512.0
+    return round(mach, 3)
+
+
+def vr60baro(msg):
+    """Vertical rate from barometric measurement, this value may be very noisy.
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS60) string
+
+    Returns:
+        int: vertical rate in feet/minutes
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[34] == '0':
+        return None
+
+    sign = d[35]    # 1 -> minus
+    value = util.bin2int(d[36:45])
+
+    if sign:
+        value = value - 512
+
+    roc = value * 32   # feet/min
+    return roc
+
+
+def vr60ins(msg):
+    """Vertical rate messured by onbard equiments (IRS, AHRS)
+
+    Args:
+        msg (String): 28 bytes hexadecimal message (BDS60) string
+
+    Returns:
+        int: vertical rate in feet/minutes
+    """
+    d = util.hex2bin(data(msg))
+
+    if d[45] == '0':
+        return None
+
+    sign = d[46]    # 1 -> minus
+    value = util.bin2int(d[47:56])
+
+    if sign:
+        value = value - 512
+
+    roc = value * 32   # feet/min
+    return roc
+
+
+def BDS(msg):
+    """Estimate the most likely BDS code of an message
+
+    Args:
+        msg (String): 28 bytes hexadecimal message string
+
+    Returns:
+        String or None: Version: "BDS20", "BDS40", "BDS50", or "BDS60". Or None, if nothing matched
+    """
+
+    if isnull(msg):
+        return None
+
+    is17 = isBDS17(msg)
+    is20 = isBDS20(msg)
+    is40 = isBDS40(msg)
+    is44 = isBDS44(msg)
+    is44rev = isBDS44(msg, rev=True)
+    is50 = isBDS50(msg)
+    is53 = isBDS53(msg)
+    is60 = isBDS60(msg)
+
+    BDS = ["BDS17", "BDS20", "BDS40", "BDS44", "BDS44REV", "BDS50", "BDS53", "BDS60"]
+    isBDS = [is17, is20, is40, is44, is44rev, is50, is53, is60]
+
+    if sum(isBDS) == 0:
+        return None
+    elif sum(isBDS) == 1:
+        return BDS[isBDS.index(True)]
+    else:
+        return [bds for (bds, i) in zip(BDS, isBDS) if i]