def capability(msg):
"""Decode transponder capability.
Args:
msg (str): 14 hexdigits string
Returns:
int, str: transponder capability, description
"""
msgbin = common.hex2bin(msg)
ca = common.bin2int(msgbin[5:8])
if ca == 0:
text = "level 1 transponder"
elif ca == 4:
text = "level 2 transponder, ability to set CA to 7, on ground"
elif ca == 5:
text = "level 2 transponder, ability to set CA to 7, airborne"
elif ca == 6:
text = "evel 2 transponder, ability to set CA to 7, either airborne or ground"
elif ca == 7:
text = "Downlink Request value is 0,or the Flight Status is 2, 3, 4 or 5, either airborne or on the ground"
else:
text = None
return ca, text
def is30(msg):
"""Check if a message is likely to be BDS code 2,0
Args:
msg (str): 28 hexdigits string
Returns:
bool: True or False
"""
if common.allzeros(msg):
return False
d = common.hex2bin(common.data(msg))
if d[0:8] != "00110000":
return False
# threat type 3 not assigned
if d[28:30] == "11":
return False
# reserved for ACAS III, in far future
if common.bin2int(d[15:22]) >= 48:
return False
return True
def temp44(msg):
"""Static air temperature.
Args:
msg (str): 28 hexdigits string
Returns:
float, float: temperature and alternative temperature in Celsius degree.
Note: Two values returns due to what seems to be an inconsistency
error in ICAO 9871 (2008) Appendix A-67.
"""
d = common.hex2bin(common.data(msg))
sign = int(d[23])
value = common.bin2int(d[24:34])
if sign:
value = value - 1024
temp = value * 0.25 # celsius
temp = round(temp, 2)
temp_alternative = value * 0.125 # celsius
temp_alternative = round(temp_alternative, 3)
return temp, temp_alternative
def is20(msg):
"""Check if a message is likely to be BDS code 2,0
Args:
msg (str): 28 hexdigits string
Returns:
bool: True or False
"""
if common.allzeros(msg):
return False
d = common.hex2bin(common.data(msg))
if d[0:8] != "00100000":
return False
# allow empty callsign
if common.bin2int(d[8:56]) == 0
return True
if "#" in cs20(msg):
return False
return True
def sil(msg, version):
"""Calculate SIL, Surveillance Integrity Level
Args:
msg (str): 28 hexdigits string with TC = 29, 31
Returns:
int or string: Probability of exceeding Horizontal Radius of Containment RCu
int or string: Probability of exceeding Vertical Integrity Containment Region VPL
string: SIL supplement based on per "hour" or "sample", or 'unknown'
"""
tc = typecode(msg)
if tc not in [29, 31]:
raise RuntimeError(
"%s: Not a target state and status message, \
or operation status message, expecting TC = 29 or 31"
% msg
)
msgbin = common.hex2bin(msg)
if tc == 29:
SIL = common.bin2int(msgbin[76:78])
elif tc == 31:
SIL = common.bin2int(msgbin[82:84])
try:
PE_RCu = uncertainty.SIL[SIL]["PE_RCu"]
PE_VPL = uncertainty.SIL[SIL]["PE_VPL"]
except KeyError:
PE_RCu, PE_VPL = uncertainty.NA, uncertainty.NA
base = "unknown"
if version == 2:
if tc == 29:
SIL_SUP = common.bin2int(msgbin[39])
elif tc == 31:
SIL_SUP = common.bin2int(msgbin[86])
if SIL_SUP == 0:
base = "hour"
elif SIL_SUP == 1:
base = "sample"
return PE_RCu, PE_VPL, base
def airborne_position_with_ref(msg, lat_ref, lon_ref):
"""Decode airborne position with only one message,
knowing reference nearby location, such as previously calculated location,
ground station, or airport location, etc. The reference position shall
be with in 180NM of the true position.
Args:
msg (str): even message (28 hexdigits)
lat_ref: previous known latitude
lon_ref: previous known longitude
Returns:
(float, float): (latitude, longitude) of the aircraft
"""
mb = common.hex2bin(msg)[32:]
cprlat = common.bin2int(mb[22:39]) / 131072
cprlon = common.bin2int(mb[39:56]) / 131072
i = int(mb[21])
d_lat = 360 / 59 if i else 360 / 60
j = common.floor(lat_ref / d_lat) + common.floor(
0.5 + ((lat_ref % d_lat) / d_lat) - cprlat
)
lat = d_lat * (j + cprlat)
ni = common.cprNL(lat) - i
if ni > 0:
d_lon = 360 / ni
else:
d_lon = 360
m = common.floor(lon_ref / d_lon) + common.floor(
0.5 + ((lon_ref % d_lon) / d_lon) - cprlon
)
lon = d_lon * (m + cprlon)
return round(lat, 5), round(lon, 5)
def wind44(msg):
"""Wind speed and direction.
Args:
msg (str): 28 hexdigits string
Returns:
(int, float): speed (kt), direction (degree)
"""
d = common.hex2bin(common.data(msg))
status = int(d[4])
if not status:
return None, None
speed = common.bin2int(d[5:14]) # knots
direction = common.bin2int(d[14:23]) * 180 / 256 # degree
return round(speed, 0), round(direction, 1)
def wind44(msg):
"""Wind speed and direction.
Args:
msg (String): 28 bytes hexadecimal message string
Returns:
(int, float): speed (kt), direction (degree)
"""
d = common.hex2bin(common.data(msg))
status = int(d[4])
if not status:
return None, None
speed = common.bin2int(d[5:14]) # knots
direction = common.bin2int(d[14:23]) * 180.0 / 256.0 # degree
return round(speed, 0), round(direction, 1)
def is40(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 common.allzeros(msg):
return False
d = common.hex2bin(common.data(msg))
# status bit 1, 14, and 27
if common.wrongstatus(d, 1, 2, 13):
return False
if common.wrongstatus(d, 14, 15, 26):
return False
if common.wrongstatus(d, 27, 28, 39):
return False
if common.wrongstatus(d, 48, 49, 51):
return False
if common.wrongstatus(d, 54, 55, 56):
return False
# bits 40-47 and 52-53 shall all be zero
if common.bin2int(d[39:47]) != 0:
return False
if common.bin2int(d[51:53]) != 0:
return False
return True
def is45(msg):
"""Check if a message is likely to be BDS code 4,5.
Meteorological hazard report
Args:
msg (str): 28 hexdigits string
Returns:
bool: True or False
"""
if common.allzeros(msg):
return False
d = common.hex2bin(common.data(msg))
# status bit 1, 4, 7, 10, 13, 16, 27, 39
if common.wrongstatus(d, 1, 2, 3):
return False
if common.wrongstatus(d, 4, 5, 6):
return False
if common.wrongstatus(d, 7, 8, 9):
return False
if common.wrongstatus(d, 10, 11, 12):
return False
if common.wrongstatus(d, 13, 14, 15):
return False
if common.wrongstatus(d, 16, 17, 26):
return False
if common.wrongstatus(d, 27, 28, 38):
return False
if common.wrongstatus(d, 39, 40, 51):
return False
# reserved
if common.bin2int(d[51:56]) != 0:
return False
temp = temp45(msg)
if temp:
if temp > 60 or temp < -80:
return False
return True
def target_angle(msg):
"""Decode target heading/track angle.
Args:
msg (str): 28 bytes hexadecimal message string
Returns:
int: Target angle (degree)
string: Angle type ('Heading' or 'Track')
string: Source ('MCP/FCU', 'Autopilot Mode' or 'FMS/RNAV')
"""
if common.typecode(msg) != 29:
raise RuntimeError("%s: Not a target state and status message, expecting TC=29" % msg)
mb = common.hex2bin(msg)[32:]
subtype = common.bin2int(mb[5:7])
if subtype == 1:
raise RuntimeError("%s: ADS-B version 2 target state and status message does not contain target angle, use selected heading instead" % msg)
angle_avail = common.bin2int(mb[25:27])
if angle_avail == 0:
angle = None
else:
angle = common.bin2int(mb[27:36])
if angle_avail == 1:
angle_source = "MCP/FCU"
elif angle_avail == 2:
angle_source = "Autopilot mode"
else:
angle_source = "FMS/RNAV"
angle_type = "Heading" if int(mb[36]) else "Track"
return angle, angle_type, angle_source
def target_altitude(msg):
"""Decode target altitude.
Args:
msg (str): 28 hexdigits string
Returns:
int: Target altitude (ft)
string: Source ('MCP/FCU', 'Holding mode' or 'FMS/RNAV')
string: Altitude reference, either pressure altitude or barometric corrected altitude ('FL' or 'MSL')
"""
if common.typecode(msg) != 29:
raise RuntimeError("%s: Not a target state and status message, expecting TC=29" % msg)
mb = common.hex2bin(msg)[32:]
subtype = common.bin2int(mb[5:7])
if subtype == 1:
raise RuntimeError("%s: ADS-B version 2 target state and status message does not contain target altitude, use selected altitude instead" % msg)
alt_avail = common.bin2int(mb[7:9])
if alt_avail == 0:
return None
elif alt_avail == 1:
alt_source = "MCP/FCU"
elif alt_avail == 2:
alt_source = "Holding mode"
else:
alt_source = "FMS/RNAV"
alt_ref = "FL" if int(mb[9]) == 0 else "MSL"
alt = -1000 + common.bin2int(mb[15:25]) * 100
return alt, alt_source, alt_ref
def um(msg):
"""Decode utility message.
Utility message contains interrogator identifier and reservation type.
Args:
msg (str): 14 hexdigits string
Returns:
int, str: interrogator identifier code that triggered the reply, and
reservation type made by the interrogator
"""
msgbin = common.hex2bin(msg)
iis = common.bin2int(msgbin[13:17])
ids = common.bin2int(msgbin[17:19])
if ids == 0:
ids_text = None
if ids == 1:
ids_text = "Comm-B interrogator identifier code"
if ids == 2:
ids_text = "Comm-C interrogator identifier code"
if ids == 3:
ids_text = "Comm-D interrogator identifier code"
return iis, ids, ids_text
def p45(msg):
"""Average static pressure.
Args:
msg (str): 28 hexdigits string
Returns:
int: static pressure in hPa
"""
d = common.hex2bin(common.data(msg))
if d[26] == "0":
return None
p = common.bin2int(d[27:38]) # hPa
return p
def rh45(msg):
"""Radio height.
Args:
msg (String): 28 bytes hexadecimal message string
Returns:
int: radio height in ft
"""
d = common.hex2bin(common.data(msg))
if d[38] == "0":
return None
rh = common.bin2int(d[39:51]) * 16
return rh
def p45(msg):
"""Average static pressure.
Args:
msg (String): 28 bytes hexadecimal message string
Returns:
int: static pressure in hPa
"""
d = common.hex2bin(common.data(msg))
if d[26] == "0":
return None
p = common.bin2int(d[27:38]) # hPa
return p
def rh45(msg):
"""Radio height.
Args:
msg (str): 28 hexdigits string
Returns:
int: radio height in ft
"""
d = common.hex2bin(common.data(msg))
if d[38] == "0":
return None
rh = common.bin2int(d[39:51]) * 16
return rh
def gs50(msg):
"""Ground speed, BDS 5,0 message
Args:
msg (str): 28 hexdigits string
Returns:
int: ground speed in knots
"""
d = common.hex2bin(common.data(msg))
if d[23] == "0":
return None
spd = common.bin2int(d[24:34]) * 2 # kts
return spd
def tas50(msg):
"""Aircraft true airspeed, BDS 5,0 message
Args:
msg (str): 28 hexdigits string
Returns:
int: true airspeed in knots
"""
d = common.hex2bin(common.data(msg))
if d[45] == "0":
return None
tas = common.bin2int(d[46:56]) * 2 # kts
return tas
def mach60(msg):
"""Aircraft MACH number
Args:
msg (str): 28 hexdigits string
Returns:
float: MACH number
"""
d = common.hex2bin(common.data(msg))
if d[23] == "0":
return None
mach = common.bin2int(d[24:34]) * 2.048 / 512.0
return round(mach, 3)
def wv45(msg):
"""Wake vortex.
Args:
msg (str): 28 hexdigits string
Returns:
int: Wake vortex level. 0=NIL, 1=Light, 2=Moderate, 3=Severe
"""
d = common.hex2bin(common.data(msg))
if d[12] == "0":
return None
ws = common.bin2int(d[13:15])
return ws
def tas53(msg):
"""Aircraft true airspeed, BDS 5,3 message
Args:
msg (String): 28 bytes hexadecimal message
Returns:
float: true airspeed in knots
"""
d = common.hex2bin(common.data(msg))
if d[33] == "0":
return None
tas = common.bin2int(d[34:46]) * 0.5 # kts
return round(tas, 1)
def ias53(msg):
"""Indicated airspeed, DBS 5,3 message
Args:
msg (String): 28 bytes hexadecimal message
Returns:
int: indicated arispeed in knots
"""
d = common.hex2bin(common.data(msg))
if d[12] == "0":
return None
ias = common.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 = common.hex2bin(common.data(msg))
if d[23] == "0":
return None
mach = common.bin2int(d[24:33]) * 0.008
return round(mach, 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 = common.hex2bin(common.data(msg))
if d[45] == "0":
return None
tas = common.bin2int(d[46:56]) * 2 # kts
return tas
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 = common.hex2bin(common.data(msg))
if d[23] == "0":
return None
spd = common.bin2int(d[24:34]) * 2 # kts
return spd
def mb45(msg):
"""Microburst.
Args:
msg (str): 28 hexdigits string
Returns:
int: Microburst level. 0=NIL, 1=Light, 2=Moderate, 3=Severe
"""
d = common.hex2bin(common.data(msg))
if d[6] == "0":
return None
mb = common.bin2int(d[7:9])
return mb
def ws45(msg):
"""Wind shear.
Args:
msg (str): 28 hexdigits string
Returns:
int: Wind shear level. 0=NIL, 1=Light, 2=Moderate, 3=Severe
"""
d = common.hex2bin(common.data(msg))
if d[3] == "0":
return None
ws = common.bin2int(d[4:6])
return ws
def ias60(msg):
"""Indicated airspeed
Args:
msg (str): 28 hexdigits string
Returns:
int: indicated airspeed in knots
"""
d = common.hex2bin(common.data(msg))
if d[12] == "0":
return None
ias = common.bin2int(d[13:23]) # kts
return ias
def turb45(msg):
"""Turbulence.
Args:
msg (str): 28 hexdigits string
Returns:
int: Turbulence level. 0=NIL, 1=Light, 2=Moderate, 3=Severe
"""
d = common.hex2bin(common.data(msg))
if d[0] == "0":
return None
turb = common.bin2int(d[1:3])
return turb