MultiPSK incorrectly decoding Inmarsat-C bulletin board.

dlwtrunked

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The decoding software MultiPSK when decoding INMARSAT bulletins boards has something that appears *very wrong*. The listing of transmissions of stations in various regions is not such but is instead a transmission of LES on the same satellite. the software falsely assigns a region and an erroneous LES number when it states one.
*Other software I have correctly decodes it from the data and on the 2 satellites that I see but MultiPSK wrongly decodes and watching test messages on individual channels indicates the other software is correct.

For example (MultiPSk decode in quotes, mine after after):

Network Version: 2ØØ / Number of LES: 6
"1: Region: POR / LES: Ø / Status: 3ØØ bps return link / Spare satellite / Out of service / Clear / Terrestrial links open / Alerting supported / Services: ALERT (Maritime Distress Alerting / SafetyNET Traffic / STD-C (Inmarsat-C Traffic) / Enhanced data reporting / Closed Network / FleetNET Traffic / LES TDM channel number: 11818"

This is LES 001 (Southbury, CT) on channel 11818 (1539.545). 11808*0.0025+1510=1539.545

"2: Region: AOR-E / LES: Ø / Status: 3ØØ bps return link / Spare satellite / Out of service / Clear / Terrestrial links open / Alerting supported / Services: ALERT (Maritime Distress Alerting / SafetyNET Traffic / STD-C (Inmarsat-C Traffic) / Store & Forward / Enhanced data reporting / Closed Network / FleetNET Traffic / LES TDM channel number: 11822"

This is LES 002 (STRATOS CSAT-Status Global-Burum, Netherlands) on channel 11822 (1539.555).

"
3: Region: IOR / LES: Ø / Status: 3ØØ bps return link / Spare satellite / Out of service / Clear / Terrestrial links open / Alerting supported / Services: ALERT (Maritime Distress Alerting / SafetyNET Traffic / STD-C (Inmarsat-C Traffic) / Store & Forward / Enhanced data reporting / Closed Network / FleetNET Traffic / LES TDM channel number: 11874"

This is LES 003 (KDDI, YAM-Yamaguchi, Japan) on channel 11874 (1539.685).


"4: Region: AOR-W / LES: 32 / Status: 3ØØ bps return link / Spare satellite / Out of service / Clear / Terrestrial links open / Alerting supported / Services: ALERT (Maritime Distress Alerting / SafetyNET Traffic / STD-C (Inmarsat-C Traffic) / Store & Forward / Enhanced data reporting / Closed Network / FleetNET Traffic / LES TDM channel number: 11826"

This is LES 004 (not LES 32 but is Eik LES-Eik, Norway) on channel 11826 (1539.565).

"
5: Region: AOR-W / NCS: 48 / Status: 3ØØ bps return link / Spare satellite / Out of service / Clear / Terrestrial links open / Alerting supported / Services: ALERT (Maritime Distress Alerting / SafetyNET Traffic / STD-C (Inmarsat-C Traffic) / Store & Forward / Enhanced data reporting / Closed Network / FleetNET Traffic / LES TDM channel number: 11834'

This is LES 012 (not an NCS but instead NL Burum LES-Burum, Netherlands) on channel 11834 (1539.585).

"
6: Region: POR / LES: 4Ø / Status: 3ØØ bps return link / Spare satellite / Out of service / Clear / Terrestrial links open / Alerting supported / Services: ALERT (Maritime Distress Alerting / SafetyNET Traffic / STD-C (Inmarsat-C Traffic) / Store & Forward / Enhanced data reporting / Closed Network / FleetNET Traffic / LES TDM channel number: 1181Ø"

This is LES 021 (ASG 21 LES-Ausguel, France) on channel 11810 (1539.525).

Note that I think the status indicated are also in errors: all above are Operational/In service, not Spare/Out of service--other software, simultaneously used, correctly decodes that.

The NCS (LES 044) for this satellite is on 1537.700 and that is in the transmission.
Note the LES are often remote uplinked from other locations than there location identified.
Also, LES number are properly displayed as octal so that the first digit indicated a region number.

The software std-c does better though its look-up table for LES sites is inaccurate. "004" appears to be Eik, Norway and not Southbury, CT.
 

ka3jjz

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MultiPSK has a very active groups.io reflector where you can get support. I doubt that Patrick even knows about this site (even tho he should...)

Anyway join up here and let Patrick have a go at this...


Mike
 

dlwtrunked

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MultiPSK has a very active groups.io reflector where you can get support. I doubt that Patrick even knows about this site (even tho he should...)

Anyway join up here and let Patrick have a go at this...


Mike
I already attempted to join there but they have not let me in yet.
I also signed up some years ago and they never completed the process to let me post so I let things go for a while (I was going to tell them how to decode Inm-D+/IsatM2M Bulletin Board which I reverse engineering with no information).
It is a rather serious error in the decoding as it gives rise to a lot of erroneous information.
 

morfis

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Patrick also has his e-mail address on his website if you'd rather not mess about with crap like farceblog
 

dlwtrunked

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Patrick also has his e-mail address on his website if you'd rather not mess about with crap like farceblog
I looked for one earlier there but only found a directive to post to the groupio group.
 

dlwtrunked

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I have been in contact with Patrick and a new release today of MultiPSK fixed the problem and is working well.
 
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