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 = hex2bin(data(msg))
if not rev:
status = int(d[4])
if not status:
return None
speed = bin2int(d[5:14]) # knots
direction = 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 = bin2int(d[5:14]) # knots
direction = bin2int(d[15:23]) * 180.0 / 128.0 # degree
return round(speed, 0), round(direction, 1)
def nac_p(msg):
"""Calculate NACp, Navigation Accuracy Category - Position
Args:
msg (string): 28 bytes hexadecimal message string, TC = 29 or 31
Returns:
int or string: 95% horizontal accuracy bounds, Estimated Position Uncertainty
int or string: 95% vertical accuracy bounds, Vertical Estimated Position Uncertainty
"""
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)
nacp_df = pd.read_csv(
'/home/josmilrom/Libraries/pyModeS/pyModeS/decoder/adsb_ua_parameters/NACp.csv',
sep=',')
if tc == 29:
nac_p = common.bin2int(msgbin[71:75])
nacp_df_extract = nacp_df[nacp_df.NACp == nac_p]
elif tc == 31:
nac_p = common.bin2int(msgbin[76:80])
nacp_df_extract = nacp_df[nacp_df.NACp == nac_p]
HFU = nacp_df_extract['HFU'][0]
VEPU = nacp_df_extract['VEPU'][0]
return HFU, VEPU
def is10(msg):
"""Check if a message is likely to be BDS code 1,0
Args:
msg (String): 28 bytes hexadecimal message string
Returns:
bool: True or False
"""
if allzeros(msg):
return False
d = hex2bin(data(msg))
# first 8 bits must be 0x10
if d[0:8] != '00010000':
return False
# bit 10 to 14 are reserved
if bin2int(d[9:14]) != 0:
return False
# overlay capabilty conflict
if d[14] == '1' and bin2int(d[16:23]) < 5:
return False
if d[14] == '0' and bin2int(d[16:23]) > 4:
return False
return True
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 = hex2bin(data(msg))
if not rev:
if d[34] == '0':
return None
p = bin2int(d[35:46]) # hPa
else:
if d[35] == '0':
return None
p = 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 = hex2bin(data(msg))
if not rev:
if d[49] == '0':
return None
hm = bin2int(d[50:56]) * 100.0 / 64 # %
else:
if d[48] == '0':
return None
hm = bin2int(d[49:56]) # %
return round(hm, 1)
def nac_p(msg):
"""Calculate NACp, Navigation Accuracy Category - Position
Args:
msg (string): 28 bytes hexadecimal message string, TC = 29 or 31
Returns:
int or string: 95% horizontal accuracy bounds, Estimated Position Uncertainty
int or string: 95% vertical accuracy bounds, Vertical Estimated Position Uncertainty
"""
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:
NACp = common.bin2int(msgbin[71:75])
elif tc == 31:
NACp = common.bin2int(msgbin[76:80])
try:
EPU = uncertainty.NACp[NACp]["EPU"]
VEPU = uncertainty.NACp[NACp]["VEPU"]
except KeyError:
EPU, VEPU = uncertainty.NA, uncertainty.NA
return EPU, VEPU
def altitude(msg):
"""Decode aircraft altitude
Args:
msg (string): 28 bytes hexadecimal message string
Returns:
int: altitude in feet
"""
tc = common.typecode(msg)
if tc < 9 or tc == 19 or tc > 22:
raise RuntimeError("%s: Not a airborn position message" % msg)
mb = common.hex2bin(msg)[32:]
if tc < 19:
# barometric altitude
q = mb[15]
if q:
n = common.bin2int(mb[8:15] + mb[16:20])
alt = n * 25 - 1000
else:
alt = None
else:
# GNSS altitude, meters -> feet
alt = common.bin2int(mb[8:20]) * 3.28084
return alt
def airborne_position(msg0, msg1, t0, t1):
"""Decode airborn position from a pair of even and odd position message
Args:
msg0 (string): even message (28 bytes hexadecimal string)
msg1 (string): odd message (28 bytes hexadecimal string)
t0 (int): timestamps for the even message
t1 (int): timestamps for the odd message
Returns:
(float, float): (latitude, longitude) of the aircraft
"""
mb0 = common.hex2bin(msg0)[32:]
mb1 = common.hex2bin(msg1)[32:]
# 131072 is 2^17, since CPR lat and lon are 17 bits each.
cprlat_even = common.bin2int(mb0[22:39]) / 131072.0
cprlon_even = common.bin2int(mb0[39:56]) / 131072.0
cprlat_odd = common.bin2int(mb1[22:39]) / 131072.0
cprlon_odd = common.bin2int(mb1[39:56]) / 131072.0
air_d_lat_even = 360.0 / 60
air_d_lat_odd = 360.0 / 59
# compute latitude index 'j'
j = common.floor(59 * cprlat_even - 60 * cprlat_odd + 0.5)
lat_even = float(air_d_lat_even * (j % 60 + cprlat_even))
lat_odd = float(air_d_lat_odd * (j % 59 + cprlat_odd))
if lat_even >= 270:
lat_even = lat_even - 360
if lat_odd >= 270:
lat_odd = lat_odd - 360
# check if both are in the same latidude zone, exit if not
if common.cprNL(lat_even) != common.cprNL(lat_odd):
return None
# compute ni, longitude index m, and longitude
if (t0 > t1):
lat = lat_even
nl = common.cprNL(lat)
ni = max(common.cprNL(lat) - 0, 1)
m = common.floor(cprlon_even * (nl - 1) - cprlon_odd * nl + 0.5)
lon = (360.0 / ni) * (m % ni + cprlon_even)
else:
lat = lat_odd
nl = common.cprNL(lat)
ni = max(common.cprNL(lat) - 1, 1)
m = common.floor(cprlon_even * (nl - 1) - cprlon_odd * nl + 0.5)
lon = (360.0 / ni) * (m % ni + cprlon_odd)
if lon > 180:
lon = lon - 360
return round(lat, 5), round(lon, 5)
def surface_velocity(msg, rtn_sources=False):
"""Decode surface velocity from from a surface position message
Args:
msg (string): 28 bytes hexadecimal message string
rtn_source (boolean): If the function will return
the sources for direction of travel and vertical
rate. This will change the return value from a four
element array to a six element array.
Returns:
(int, float, int, string, string, None): speed (kt),
ground track (degree), None for rate of climb/descend (ft/min),
and speed type ('GS' for ground speed), direction source
('true_north' for ground track / true north as reference),
None rate of climb/descent source.
"""
if common.typecode(msg) < 5 or common.typecode(msg) > 8:
raise RuntimeError("%s: Not a surface message, expecting 5<TC<8" % msg)
mb = common.hex2bin(msg)[32:]
# ground track
trk_status = int(mb[12])
if trk_status == 1:
trk = common.bin2int(mb[13:20]) * 360.0 / 128.0
trk = round(trk, 1)
else:
trk = None
# ground movement / speed
mov = common.bin2int(mb[5:12])
if mov == 0 or mov > 124:
spd = None
elif mov == 1:
spd = 0
elif mov == 124:
spd = 175
else:
movs = [2, 9, 13, 39, 94, 109, 124]
kts = [0.125, 1, 2, 15, 70, 100, 175]
i = next(m[0] for m in enumerate(movs) if m[1] > mov)
step = (kts[i] - kts[i - 1]) * 1.0 / (movs[i] - movs[i - 1])
spd = kts[i - 1] + (mov - movs[i - 1]) * step
spd = round(spd, 2)
if rtn_sources:
return spd, trk, 0, "GS", "true_north", None
else:
return spd, trk, 0, "GS"
def callsign(msg):
"""Aircraft callsign
Args:
msg (string): 28 bytes hexadecimal message string
Returns:
string: callsign
"""
if common.typecode(msg) < 1 or common.typecode(msg) > 4:
raise RuntimeError("%s: Not a identification message" % msg)
chars = '#ABCDEFGHIJKLMNOPQRSTUVWXYZ#####_###############0123456789######'
msgbin = common.hex2bin(msg)
csbin = msgbin[40:96]
cs = ''
cs += chars[common.bin2int(csbin[0:6])]
cs += chars[common.bin2int(csbin[6:12])]
cs += chars[common.bin2int(csbin[12:18])]
cs += chars[common.bin2int(csbin[18:24])]
cs += chars[common.bin2int(csbin[24:30])]
cs += chars[common.bin2int(csbin[30:36])]
cs += chars[common.bin2int(csbin[36:42])]
cs += chars[common.bin2int(csbin[42:48])]
# clean string, remove spaces and marks, if any.
# cs = cs.replace('_', '')
cs = cs.replace('#', '')
return cs
def nac_v(msg):
"""Calculate NACv, Navigation Accuracy Category - Velocity
Args:
msg (string): 28 bytes hexadecimal message string, TC = 19
Returns:
int or string: 95% horizontal accuracy bounds for velocity, Horizontal Figure of Merit
int or string: 95% vertical accuracy bounds for velocity, Vertical Figure of Merit
"""
tc = typecode(msg)
if tc != 19:
raise RuntimeError(
"%s: Not an airborne velocity message, expecting TC = 19" % msg)
nacv_df = pd.read_csv(
'/home/josmilrom/Libraries/pyModeS/pyModeS/decoder/adsb_ua_parameters/NACv.csv',
sep=',')
msgbin = common.hex2bin(msg)
nac_v = common.bin2int(msgbin[42:45])
nacv_df_extract = nacv_df[nacv_df.NACv == nac_v]
HFOMr = nacv_df_extract['HFOMr'][0]
VFOMr = nacv_df_extract['VFOMr'][0]
return HFOMr, VFOMr
def nuc_v(msg):
"""Calculate NUCv, Navigation Uncertainty Category - Velocity (ADS-B version 1)
Args:
msg (string): 28 bytes hexadecimal message string,
Returns:
int or string: 95% Horizontal Velocity Error
int or string: 95% Vertical Velocity Error
"""
tc = typecode(msg)
if tc != 19:
raise RuntimeError(
"%s: Not an airborne velocity message, expecting TC = 19" % msg)
msgbin = common.hex2bin(msg)
NUCv = common.bin2int(msgbin[42:45])
try:
HVE = uncertainty.NUCv[NUCv]["HVE"]
VVE = uncertainty.NUCv[NUCv]["VVE"]
except KeyError:
HVE, VVE = uncertainty.NA, uncertainty.NA
return HVE, VVE
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 = hex2bin(data(msg))
if d[0] == '0':
return None
sign = int(d[1]) # 1 -> west
value = 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, 3)
def is30(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 allzeros(msg):
return False
d = hex2bin(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 bin2int(d[15:22]) >= 48:
return False
return True
def is17(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 allzeros(msg):
return False
d = hex2bin(data(msg))
if bin2int(d[28:56]) != 0:
return 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', 'BDS08', 'BDS09', 'BDS20']).issubset(caps):
return False
return True
def temp44(msg):
"""Static air temperature.
Args:
msg (String): 28 bytes hexadecimal message string
Returns:
float, float: temperature and alternative temperature in Celsius degree.
Note: Two values returns due to what seems to be an inconsistancy
error in ICAO 9871 (2008) Appendix A-67.
"""
d = hex2bin(data(msg))
sign = int(d[23])
value = 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 nac_v(msg):
"""Calculate NACv, Navigation Accuracy Category - Velocity
Args:
msg (string): 28 bytes hexadecimal message string, TC = 19
Returns:
int or string: 95% horizontal accuracy bounds for velocity, Horizontal Figure of Merit
int or string: 95% vertical accuracy bounds for velocity, Vertical Figure of Merit
"""
tc = typecode(msg)
if tc != 19:
raise RuntimeError(
"%s: Not an airborne velocity message, expecting TC = 19" % msg)
msgbin = common.hex2bin(msg)
NACv = common.bin2int(msgbin[42:45])
try:
HFOMr = uncertainty.NACv[NACv]["HFOMr"]
VFOMr = uncertainty.NACv[NACv]["VFOMr"]
except KeyError:
HFOMr, VFOMr = uncertainty.NA, uncertainty.NA
return HFOMr, VFOMr
def altitude(msg):
"""Decode aircraft altitude
Args:
msg (string): 28 bytes hexadecimal message string
Returns:
int: altitude in feet
"""
tc = typecode(msg)
if tc < 5 or tc == 19 or tc > 22:
raise RuntimeError("%s: Not a position message" % msg)
if tc >= 5 and tc <= 8:
# surface position, altitude 0
return 0
msgbin = common.hex2bin(msg)
q = msgbin[47]
if q:
n = common.bin2int(msgbin[40:47] + msgbin[48:52])
alt = n * 25 - 1000
return alt
else:
return None
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 = hex2bin(data(msg))
if d[11] == '0':
return None
sign = int(d[12]) # 1 -> west
value = 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, 3)
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 = hex2bin(data(msg))
if d[0] == '0':
return None
sign = int(d[1]) # 1 -> west
value = 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, 3)
def sil(msg, version):
"""Calculate SIL, Surveillance Integrity Level
Args:
msg (string): 28 bytes hexadecimal message 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 "per sample"
"""
tc = typecode(msg)
if tc not in [29, 31]:
raise RuntimeError("%s: Not a target state and status messag, \
or operation status message, expecting TC = 29 or 31"
% msg)
sil_df = pd.read_csv(
'/home/josmilrom/Libraries/pyModeS/pyModeS/decoder/adsb_ua_parameters/SIL.csv',
sep=',')
msgbin = common.hex2bin(msg)
if tc == 29:
sil = common.bin2int(msgbin[76:78])
elif tc == 31:
sil = common.bin2int(msg[82:84])
sil_df_extract = sil_df[sil_df.NACv == sil]
PR_RCu = sil_df_extract['PR_RCu'][0]
PE_VPL = sil_df_extract['PE_VPL'][0]
if version == 1:
return PR_RCu, PE_VPL
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 = "per hour"
elif sil_sup == 1:
base = "per sample"
return PR_RCu, PE_VPL, base
def sil(msg, version):
"""Calculate SIL, Surveillance Integrity Level
Args:
msg (string): 28 bytes hexadecimal message 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 messag, \
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 surface_position_with_ref(msg, lat_ref, lon_ref):
"""Decode surface 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 45NM of the true position.
Args:
msg (string): even message (28 bytes hexadecimal string)
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]) / 131072.0
cprlon = common.bin2int(mb[39:56]) / 131072.0
i = int(mb[21])
d_lat = 90.0 / 59 if i else 90.0 / 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 = 90.0 / ni
else:
d_lon = 90.0
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 surface_velocity(msg):
"""Decode surface velocity from from a surface position message
Args:
msg (string): 28 bytes hexadecimal message string
Returns:
(int, float, int, string): speed (kt), ground track (degree),
rate of climb/descend (ft/min), and speed type
('GS' for ground speed, 'AS' for airspeed)
"""
if common.typecode(msg) < 5 or common.typecode(msg) > 8:
raise RuntimeError("%s: Not a surface message, expecting 5<TC<8" % msg)
mb = common.hex2bin(msg)[32:]
# ground track
trk_status = int(mb[12])
if trk_status == 1:
trk = common.bin2int(mb[13:20]) * 360.0 / 128.0
trk = round(trk, 1)
else:
trk = None
# ground movment / speed
mov = common.bin2int(mb[5:12])
if mov == 0 or mov > 124:
spd = None
elif mov == 1:
spd = 0
elif mov == 124:
spd = 175
else:
movs = [2, 9, 13, 39, 94, 109, 124]
kts = [0.125, 1, 2, 15, 70, 100, 175]
i = next(m[0] for m in enumerate(movs) if m[1] > mov)
step = (kts[i] - kts[i - 1]) * 1.0 / (movs[i] - movs[i - 1])
spd = kts[i - 1] + (mov - movs[i - 1]) * step
spd = round(spd, 2)
return spd, trk, 0, 'GS'
def wind44(msg):
"""Wind speed and direction.
Args:
msg (String): 28 bytes hexadecimal message string
Returns:
(int, float): speed (kt), direction (degree)
"""
d = hex2bin(data(msg))
status = int(d[4])
if not status:
return None, None
speed = bin2int(d[5:14]) # knots
direction = 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 allzeros(msg):
return False
d = hex2bin(data(msg))
# status bit 1, 14, and 27
if wrongstatus(d, 1, 2, 13):
return False
if wrongstatus(d, 14, 15, 26):
return False
if wrongstatus(d, 27, 28, 39):
return False
if wrongstatus(d, 48, 49, 51):
return False
if wrongstatus(d, 54, 55, 56):
return False
# bits 40-47 and 52-53 shall all be zero
if bin2int(d[39:47]) != 0:
return False
if 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 (String): 28 bytes hexadecimal message string
Returns:
bool: True or False
"""
if allzeros(msg):
return False
d = hex2bin(data(msg))
# status bit 1, 4, 7, 10, 13, 16, 27, 39
if wrongstatus(d, 1, 2, 3):
return False
if wrongstatus(d, 4, 5, 6):
return False
if wrongstatus(d, 7, 8, 9):
return False
if wrongstatus(d, 10, 11, 12):
return False
if wrongstatus(d, 13, 14, 15):
return False
if wrongstatus(d, 16, 17, 26):
return False
if wrongstatus(d, 27, 28, 38):
return False
if wrongstatus(d, 39, 40, 51):
return False
# reserved
if bin2int(d[51:56]) != 0:
return False
temp = temp45(msg)
if temp:
if temp > 60 or temp < -80:
return False
return True
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 = hex2bin(data(msg))
if not rev:
# if d[22] == '0':
# return None
sign = int(d[23])
value = 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 = bin2int(d[25:35])
if sign:
value = value - 1024
temp = value * 0.125 # celsius
temp = round(temp, 1)
return temp
def p45(msg):
"""Average static pressure.
Args:
msg (String): 28 bytes hexadecimal message string
Returns:
int: static pressure in hPa
"""
d = hex2bin(data(msg))
if d[26] == "0":
return None
p = 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 = hex2bin(data(msg))
if d[38] == "0":
return None
rh = bin2int(d[39:51]) * 16
return rh