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implement aprs data extensions

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This commit is contained in:
Jakob Ketterl 2019-08-17 22:04:45 +02:00
parent 82eaff5da6
commit 7e757c005c
1 changed files with 44 additions and 5 deletions
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49
owrx/aprs.py
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@ -11,6 +11,7 @@ logger = logging.getLogger(__name__)
# speed is in knots... convert to metric (km/h)
knotsToKilometers = 1.852
feetToMeters = 0.3048
milesToKilometers = 1.609344
# not sure what the correct encoding is. it seems TAPR has set utf-8 as a standard, but not everybody is following it.
encoding = "utf-8"
@ -166,7 +167,7 @@ class AprsParser(object):
if information[10] != " ":
if information[10] == "{":
# pre-calculated radio range
aprsData["range"] = 2 * 1.08 ** (ord(information[11]) - 33)
aprsData["range"] = 2 * 1.08 ** (ord(information[11]) - 33) * milesToKilometers
else:
aprsData["course"] = (ord(information[10]) - 33) * 4
# speed is in knots... convert to metric (km/h)
@ -187,16 +188,54 @@ class AprsParser(object):
"Digipeater conversion",
]
aprsData["compressionorigin"] = origins[t & 0b00000111]
aprsData["comment"] = information[13:]
comment = information[13:]
else:
aprsData = self.parseUncompressedCoordinates(information[0:19])
aprsData["type"] = "regular"
aprsData["comment"] = information[19:]
comment = information[19:]
matches = altitudeRegex.match(aprsData["comment"])
def decodeHeightGainDirectivity(comment):
res = {
"height": 2 ** int(comment[4]) * 10 * feetToMeters,
"gain": int(comment[5]),
}
directivity = int(comment[6])
if directivity == 0:
res["directivity"] = "omni"
elif 0 < directivity < 9:
res["directivity"] = directivity * 45
return res
# aprs data extensions
if len(comment) > 6:
if comment[3] == "/":
# course and speed
# for a weather report, this would be wind direction and speed
aprsData["course"] = int(comment[0:3])
aprsData["speed"] = int(comment[4:7]) * knotsToKilometers
comment = comment[7:]
elif comment[0:3] == "PHG":
# station power and effective antenna height/gain/directivity
powerCodes = [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
aprsData["power"] = powerCodes[int(comment[3])]
aprsData.update(decodeHeightGainDirectivity(comment))
comment = comment[7:]
elif comment[0:3] == "RNG":
# pre-calculated radio range
aprsData["range"] = int(comment[3:7]) * milesToKilometers
comment = comment[7:]
elif comment[0:3] == "DFS":
# direction finding signal strength and antenna height/gain
aprsData["strength"] = int(comment[3])
aprsData.update(decodeHeightGainDirectivity(comment))
comment = comment[7:]
matches = altitudeRegex.match(comment)
if matches:
aprsData["altitude"] = int(matches[2]) * feetToMeters
aprsData["comment"] = matches[1] + matches[3]
comment = matches[1] + matches[3]
aprsData["comment"] = comment
return aprsData