Topics

#ACARS #HFDL #VDL2 #HFDL #ACARS #VDL2

Chris
 

Can someone give me some guidance as to what software to use to decode ACARS and HFDL and how to contribute to this Group.

Thanks

Dick
 

Hi Chris,

As all things in file "it depends" :-)
Are you a windows or Linux user (or both)?

If you want a first quick go on these modes you can use MultiPSK, as it can decode ACARS, VDL2 and HFDL and many many more.
See: http://f6cte.free.fr/index_anglais.htm as well as this group https://groups.io/g/multipsk/topics

If you realy want to get max results my advice would be to go for decoders on Linux.
Their advantage over MultiPSK is that they will decode multiple frequencies at the same time.
I use these on my Raspberry Pi's with cheap RTL-SDR dongles:
- dumpvdl2 https://github.com/szpajder/dumpvdl2 ( IMHO has the best VDL2 features).
- vdlm2dec https://github.com/TLeconte/vdlm2dec
- acarsdec https://github.com/TLeconte/acarsdec
On windows I use PC-HFDL http://www.chbrain.dircon.co.uk/
(and the HFDL subgroup. https://acars-vdl2.groups.io/g/HFDL )
and programs from the Display-Launcher suite http://www.agenetools.com/displaylauncher/index.html

And then there is satellite traffic which can be decoded using JAERO.

Hope this helps.

As to contibuting to the group, well we are trying to ID unknown VDL2 groundstations, so if you are in an 'undocumented VDL2' part of the world we would be very happy if you could help us out.
Also see Sergio's updates in this and in the MultiPSK group.

Cheers,
Dick (the Netherlands)

Chris
 

Thanks for your reply Dick.  Some great info. there for me to get started with.

I've used PC-HFDL before and that it what I use to decode VHF/HF ACARS messages.  I thought people were using more sophisticated software to decode ACARS but it seems people are just using the usual free software you can get online from various sites.  I'm a Windows user so only Windows software I'm able to run.  There is software you might of heard of called 'W-CODE'.  That looks pretty good but it's not available to the public.  I did email the company a while back and they replied by saying yes you can have a copy ... for a ridiculous price of around £5,000 (GBP) if I remember!

I get lots of hits from receiving VHF and HF ACARS data but how much of that information is good to share with the Group I don't know?  I need to figure out what these posts from others are about when they refer to GSIF ... what is that??

Dick
 

Hi Chris,
Welcome back to aero stuff ;-)

IMHO PC-HFDL is not very good in decoding acars message.
At the time I started using PC-HFDL I already used ACARSD which gave much better results.

Never heard of 'W-CODE' before, but searching for it on the intenet I found out that it is also known as Wavecom, which is a known professional (expensive) decoder.

So for now, untill I can talk you into getting an RPi (Raspberry Pi), you can use acarsdeco2 on Windows to decode multipe acars frequencies.
see: http://xdeco.org/?page_id=42
It uses the same cheap RTL-SDR as the receiver.

As you can see in the group we don't upload logs and most of the posts are Q&A or VDL2 related.
VDL2 is the successor of ACARS which is now also known as POA (Plain Old Acars).

GSIF stands for Ground Station Information Frame.
Its function is like the squitter messages on POA and HFDL you might be familiar with. It identifies the groundstation and supplies relevant information.
MultiPSK does decode VDL2 but only in "professional mode" which becomes available after you pay a small fee.

Cheers,
Dick

Chris
 

Dick, thanks again for replying ... with more great information.

I have tried previously to install 'ACARSD' and the program 'acarsdeco2' but the install did not work.  There wasn't anything I did wrong, I just downloaded it, clicked on the executable file to install and just remember being presented with error messages about the installation.  So gave up on trying to figure out why it wouldn't install.  So focusing on VDL2 as from what you're saying it would seem as if ACARS is now old stuff ... VDL2 being the new way to go.  Are there any standalone programs that will decode VDL2 or is decoding only available when using software such as MultiPSK?  (have to say I have tried MultiPSK before but couldn't get it to work at all if I remember with my Icom IC-R8600 ... think I might of tried using an AOR 8600 Mk2 I also have but don't remember MultiPSK working)

Moving on, here's a copy of a message posted by someone else in this Group a few days ago:

17/05/20 17:37:44 UTC
Broadcast address (hexa): FFFFFF (All aircraft)
Source address (hexa): 10985A (Ground Station, delegated address [LFMN Nice Cote d'Azur France] , On the ground , command frame)
XID (Exchange Identification) frame F=0
Data (hexa): 8280001C0109383838353A31393933020200010303208480050207D8060207D8F0001F000156040120C1044C464D4EC406584141020093C504FC020000C8031B5048
Public parameters:HDLC public parameter: 8885:1993
Classes of procedures (hexa): 0001
HDLC functions (hexa): 208480
I field length TX (hexa): 07D8
I field length RX (hexa): 07D8
Private parameter set identifier: V
AVLC specific options parameter (hexa): 20
Airports covered by the ground station: LFMN NICE/COTE D'AZUR (FRANCE) 
ATN router nets: 
  * ADM identifier (hexa): 584141   User field (hexa): 020093
Station operator mask (address) (hexa): F00000
Ground station (+/- 3'): 43°42'N 007°12'E

What is all this about?  To me (and being a human being... haha) that message doesn't make much sense to me.

Paul Gulliver
 

Hi Chris,

You don't have to "install" acarsdeco2, it come in a zip file, just copy the contents to your hard drive, but it cannot be run from the.exe file but has to be run from the .bat file.

The .bat file contains the frequencies and logging details, this is my bat file

C:\Tools\AD2\acarsdeco2.exe --gain 43.9 --freq-correction -3 --freq 131525000 --freq 131725000 --freq 131825000 --http-port 8080 --udp 127.0.0.1:9742 --net 30008 --vrs-url http://127.0.0.1:80 --logfile W:\Acars_Log\Message-Log

more details on setup here http://xdeco.org/?page_id=42

I don't think there is any standalone program for VDL2 in Windows, as Dick already mentioned Multipsk is the normal method for Windows decoding, it works ok with SDR receivers, used in conjunction with software such as SDR console and vac cable multiple VDL frequencies can be decoded,

But the RPi method is the best particularly for 24/7 operation - one RPi and 2 dongles can receive all VHF acars and VDL2 messages at the same time

Paul


On 09/06/2020 at 18:21, Chris <wrl-2@...> wrote:
Dick, thanks again for replying ... with more great information.

I have tried previously to install 'ACARSD' and the program 'acarsdeco2' but the install did not work.  There wasn't anything I did wrong, I just downloaded it, clicked on the executable file to install and just remember being presented with error messages about the installation.  So gave up on trying to figure out why it wouldn't install. 

Dick
 

On Tue, Jun 9, 2020 at 07:21 PM, Chris wrote:


have to say I have tried MultiPSK before but couldn't get it to work at all if
I remember with my Icom IC-R8600 ... think I might of tried using an AOR 8600
Mk2 I also have but don't remember MultiPSK working
Well, all I can say is "join the MultiPSK group, try again and if you can't get it working ask for help but be as specific as possible". Remember many people are using MultiPSK so you should be able too.
MultiPSK does work with 'analog' receivers like the ones you mention.
But to be able to decode VDL2 the receiver needs to be able to support a wide (audio) bandwidth.
About 3 years ago I created these instruction:
http://planeplotter.pbworks.com/w/page/75894179/VDL%20mode%202
Might not be 100% up2date though..

What is all this about?
This is a GSIF decoded by MultiPSK.
The content of the "Data (hexa): " line is decoded below it.
Mainly network related parameters that are not relevant for most of us.
Interesting are these lines:
Airports covered by the ground station:
Ground station (+/- 3'): 43°42'N 007°12'E

You can learn a lot from Tomasz (author of dumpvdl2) posts.
He has great knowledge of the VDL2 message structure which is why dumpvdl2 does decode a lot more details then MultiPSK. (time to get an RPi ;-)

PS.
Just to be sure I downloaded acarsdeco2, unzipped the zip file and ran ad2.bat (like Paul said) on my Win10 64 laptop.
Works fine.

Cheers,
Dick