These updates were designed to assist those using interactive
mode to tune antennas and SDR gain.
* Add options to display distance and bearing in interactive mode
Distance and bearing instead of latitude and longitude can now be
displayed in interactive mode using the following options to
dump1090-fa and view1090-fa.
--interactive-show-distance Show aircraft distance and bearing
instead of aircraft lat/lon
(requires --lat and --lon)
--interactive-distance-units Distance units ('km', 'sm', 'nm')
(default: 'nm')"
You have to specify a reference --lat and --lon for this to
work of course.
* A new line now shows at the top of the interactive display that
has for the current sample:
Total valid aircraft count
Vidible aircraft count
Will be less than total if the screen hasn't enough lines to show
them all.
Max RSSI
Min RSSI
Mean RSSI
Max Distance
Tot: 47 Vis: 47 RSSI: Max 25.4+ Mean -29.5 Min -36.9- MaxD: 197.3nm+
* Add max distance and min/max RSSI indicators
A '+' after the distance in a row indicates it's the row with the
maximum distance.
A '+' after the RSSI in a row indicates it's the row with the highest
RSSI.
A '-' after the RSSI in a row indicates it's the row with the lowest
RSSI.
The summary line at the top of the screen always shows the values for
ALL aircraft, even those not visible. The row indicators only mark
visible rows though.
In this example, the first aircraft is both the farthest away and has
the weakest RSSI. The second aircraft has the strongest RSSI.
Tot: 47 Vis: 47 RSSI: Max 25.4+ Mean -29.5 Min -36.9- MaxD: 197.3nm+ -
Hex Mode Sqwk Flight Alt Spd Hdg Dist(nm) Bearing RSSI Msgs Ti
────────────────────────────────────────────────────────────────────────────────
A8D5A4 S2 34000 438 252 197.3+ 85 -36.1- 26 2
A39A13 S2ac 5740 FFT525 30750 439 256 98.8 68 -25.4+ 123 0
A70B23 S2ac 2744 LXJ553 43000 419 258 136.1 39 -33.6 174 0
* Finally, a new option '--interactive-callsign-filter' has been added
to allow filtering interactive by callsign. The value can be a
simple string, in which case aircraft with that string anywhere in its
callsign will be displayed, or a regular expression should you want a
more precise match.
Examples:
--interactive-callsign-filter UAL
will match all aircraft with UAL anywhere in its callsign.
--interactive-callsign-filter "^UAL"
will match only those callsigns that start with UAL.
--interactive-callsign-filter "^(UAL|AAL)"
will match only those callsigns that start with UAL or AAL.
--interactive-callsign-filter "^N[0-9]" or "^N[[:digit:]]"
will match only those callsigns that start with "N" and a number
If you need more info on regular expressions, see this link:
https://en.wikipedia.org/wiki/Regular_expression
The old matching process which tracked mode A values as pseudo-aircraft
got very, very expensive with a large number of mode A/C messages (and
with lots of single-bit errors, which seems common with a Beast doing
the reception)
Instead just count A/C messages directly into a 4096-entry array (which
is very fast) and periodically scan the mode S aircraft list to see if
we can match anything up (which is fixed overhead + cost proportional
to the number of mode S aircraft)
(except in --net-verbatim mode, where we emit them all)
Move aircraft tracking into track.[ch].
Clean up references to "interactive mode" when tracking
aircraft - we always track aircraft, even in non-interactive
mode.
since we have 8 bits spare, so there's no chance of confusing it
with an ICAO address, and we can safely use the filter table to match
future messages without also matching equivalent ICAO addresses.
Switch signalLevel back to a power measurement, don't put SNR in there.
But make it a 0.0 - 1.0 double so we're not scaling everywhere.
Adjust for the amplitude offset when calculating power.
Adapt everything else to the new scheme.
There is a danger in always using relative decoding where possible.
If there is an undetected error in the first pair of messages received,
then global CPR decoding will give a bad position, and subsequent
relative decoding will just walk around near that bad position even
though many error-free pairs of odd/even messages may have been received.
The first pair of position messages also tends to be the most error-prone, as
they are usually received at the extreme edge of receiver range.
(I see this happen at least once a day in practice)
So, instead, prefer to use global decoding when we have sufficiently recent data.
With recent data this should always be as good as relative decoding, and it
avoids getting stuck with bad data for long periods of time. If we don't have
enough recent data for a global solution, fall back to relative decoding.
If the aircraft lands or takes off, the Lat/Lon valid flags are cleared.
In the original code, this also resulted in any even/odd position
reports in the mm record being discarded This meant that the code would
require an even and odd position after the change of flight status.
The code had been modified so that any position report in the mm record
is used even if there is a change of flight status. This means there
only needs to be an even or odd after a change of FS, rather than
requiring both even and odd. The result should be earlier decoding of
position.
Updated the way socket handles are used in View1090 to maintain
compatibility between UNIX and Windows.
Added the initial attempt at a Planeplotter uploader
The modesReadFromClient() funtion is called from modesReadFromClients(),
which in turn is called from backgroundTasks(). backgroundTasks() is
called from within the main processing loop.
However, modesReadFromClient() can and does block. It attempts to read
characters from the input stream, and loops whilst there was no error.
This stalls the main RTL processing loop until an error occurs. In order
to support simultaneous local reception (via our RTL dongle) and remote
forwarding (data received from the interweb) we cannot allow this
internet read to stall.
To fix this, in modesReadFromClient() attempt to read a buffer of data
(currently 0x400 bytes). If we get a full buffer of bytes, then process
them, and attempt to read another full buffer. Keep doing thios untill
we read only a partial buffer (less than 0x400 bytes). Process the
partial buffer bytes and return.
This allows us to occasionally process data that is arriving from the
internet (which is buffered anyway in the TCP stack), without blocking
local RTL dongle decoding.
Ok - this is likely to upset some people. Up until now, the vast
majority of the code has been in just one file - dump1090.c. This file
has grown so that it was approaching of 5000 lines long, and it was
becoming unmanagable. So I've split the file into several modules,
hopefully along fairly logical boundaries. The files are :
1) dump1090.c : Basically just the main() entry function, the help
function, the RTL dongle hardware interface, and a few orphan functions
that don't really fit anywhere else.
2) mode_s.c : This contains all the mode S / ADSB decoding functions.
3) mode_ac.c : This contains all the mode A & C decoding functions
4) interactive.c : This contains all the functions to maintain an
internal list of aircraft seen over the last period, and functions to
print them out to the local console.
5) net_io.c : This contains all the network input/output functions
allowing data to be passed in/out to/from other receivers, in formats
such as SBS-1/3, Beast, AVR and JavaScript.
Hopefully this should provide an easier way forward if/when more
functions are added.
VasiliyTurchenko
Oliver Jowett
Edwin Groothuis
George Joseph
Oliver Jowett
Malcolm Robb