Outernet L-Band now carries AMSAT and ARISS weekly bulletins
The Outernet L-band feed is now carrying a condensed version of the AMSAT and ARISS weekly news files. (Global Geosat coverage except for Northern Alaska)...
Receivers are simple: http://aprs.org/outnet.html
For ARISS, I manually added a 2 char grid square to each school listed in the school schedule and am asking the outernet folks to parse out that location info and plot a 1200 km footprint on their weather globe showing where people can tune in the ARISS contacts. Then their RTL-SDR dongle could then actually be retuned to hear the contact. Just an idea...
Bob, WB4APR
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Dani EA4GPZ Sent: Saturday, October 15, 2016 7:36 AM To: amsat-bb@amsat.org Subject: Re: [amsat-bb] New Outernet L-Band service...
I hope someday a service like this will be available from an AMSAT geostationary service.
I'm pretty confident that the guys at AMSAT-DL are capable of doing this much better on the upcoming EsHail'2 than what Outernet is currently doing on Inmarsat...
They already have in mind a "DVB-S beacon"... broadcast from the ground station at Qatar ... carrying videos about Ham radio and Ham radio events on this signal.
What is more, if you have equipment to operate EsHail'2 on SSB, it's more or less easy to use either the narrowband transponder or the wideband transponder to transmit an Outernet-type signal through EsHail'2, so anyone can have a go with this.
Outernet uses 4200baud BPSK and half of the bitrate is spent for FEC. You can use a bit less bitrate to get a signal that will even pass through a conventional 2.7kHz SSB filter and you can use less bits for FEC to get increased data throughput (but more SNR required).
Dani EA4GPZ.
So cool to see this type of info delivered via geosynchronous satellite!
=============== AMSAT NEWS SERVICE ANS-297 http://amsat.org
---------- VHF Handheld Radio on ISS Failed, ARISS Contacts Moved to Kenwood Radio
~~~ {other articles follow} ~~~ ===============
It might be useful to start the body of each file with the date of publication. A viewer might come across this content some days after it was originally uploaded.
Looks great!
-Scott, K4KDR
-------------------------------------------------------------------------------- --------------------------------------------------------------------------------
-----Original Message----- From: Robert Bruninga Sent: Monday, October 24, 2016 9:53 AM To: amsat-bb@amsat.org Subject: [amsat-bb] Outernet L-Band now carries AMSAT and ARISS weeklybulletins
The Outernet L-band feed is now carrying a condensed version of the AMSAT and ARISS weekly news files. (Global Geosat coverage except for Northern Alaska)...
Receivers are simple: http://aprs.org/outnet.html
For ARISS, I manually added a 2 char grid square to each school listed in the school schedule and am asking the outernet folks to parse out that location info and plot a 1200 km footprint on their weather globe showing where people can tune in the ARISS contacts. Then their RTL-SDR dongle could then actually be retuned to hear the contact. Just an idea...
Bob, WB4APR
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Dani EA4GPZ Sent: Saturday, October 15, 2016 7:36 AM To: amsat-bb@amsat.org Subject: Re: [amsat-bb] New Outernet L-Band service...
I hope someday a service like this will be available from an AMSAT geostationary service.
I'm pretty confident that the guys at AMSAT-DL are capable of doing this much better on the upcoming EsHail'2 than what Outernet is currently doing on Inmarsat...
They already have in mind a "DVB-S beacon"... broadcast from the ground station at Qatar ... carrying videos about Ham radio and Ham radio events on this signal.
What is more, if you have equipment to operate EsHail'2 on SSB, it's more or less easy to use either the narrowband transponder or the wideband transponder to transmit an Outernet-type signal through EsHail'2, so anyone can have a go with this.
Outernet uses 4200baud BPSK and half of the bitrate is spent for FEC. You can use a bit less bitrate to get a signal that will even pass through a conventional 2.7kHz SSB filter and you can use less bits for FEC to get increased data throughput (but more SNR required).
Dani EA4GPZ
I noticed another news story from Outernet and I have some comments.
For those who don't know Outernet is a "commercial" /for the greater good, satellite downlink only service providing low bandwidth data, aimed at filling and updating a hard drive with news and info, aimed at developing nations, a free to receive data stream, for educational purposes etc. Their latest stunt/change is to downlink on 12Ghz from a Geostationary satellite, with reception without using a satellite dish, but instead just a bare LNB pointed in the direction of the geostationary satellite, using the gain of the horn inside the LNB.
News stories here: https://hackaday.com/2018/02/22/at-71572-km-you-wont-beat-this-lora-record/
https://store.outernet.is/blogs/the-official-outernet-blog/world-record
https://www.indiegogo.com/projects/lantern-a-global-satellite-data-radio
I would hesitate to recommend this system, as it is vapour-ware at the moment, and all the previous kits/hardware released have been dropped and made obsolete by changes to the broadcast. Previous broadcasts were 12Ghz geostationary, but decoded using a DVB-S tuner demodulator, then they changed to L-band low earth orbit immarsat and now they are back on geostationary, this time with a new modulation scheme making pointing easier. They are using the "LoRa" standard, basically just using a protocol that allows low signal margin decoding ( Chirp Spread Spectrum modulation (CSS) which trades data rate for sensitivity within a fixed channel bandwidth. ), similar to WSJT/PSK31 and other low data rate weak signal modes.
It is interesting they thing that a bare LNB (about 80 degree beam width) that seems to be doing the trick, although they also show pictures of patch antennas which presumably are designed for narrower beam width more suited to this.
The main caution I would have is they seem to be constantly peddling hardware, which soon becomes obsolete, without in fact any real business model to fund the venture. They claim their business model will be advertising or donations, obtained after the system catches on, on a large scale, but I have not seen any real attempt to get wide scale adoption in poor regions. They either do not have the funds or cannot get critical adoption for this one-way solution. Anyway I would encourage Amateurs to look at the "technology demonstration" they have made and consider if similar techniques could be applied to LEO or Geostationary Amateur or Emergency uses. Assuming they are still relaying the weekly AMSAT news (I have not seen any actual listing of what is actually downlinked, except for vague references to tests and some of Wikipedia) it might be a good fun project, but beware the technology is very untested and if (or when) they go bust, then the signals will stop. I have to wonder if the L-band service was a short term contract, that they can no longer pay for, and that they have fallen back to cheaper geostationary data.
If someone could set up a receiver (when they actually re-launch/start a new service) and list what is actually down linked, that would be good to know, but for now I would consider it still very much in the testing phase.
I would have thought if they were serious they would have launched a finished tested solution by now, aimed at developing nations and have it backed by advertising to make broadcasting self funding.
Dan EI9FHB
On 24/10/2016, Robert Bruninga bruninga@usna.edu wrote:
The Outernet L-band feed is now carrying a condensed version of the AMSAT and ARISS weekly news files. (Global Geosat coverage except for Northern Alaska)...
Receivers are simple: http://aprs.org/outnet.html
For ARISS, I manually added a 2 char grid square to each school listed in the school schedule and am asking the outernet folks to parse out that location info and plot a 1200 km footprint on their weather globe showing where people can tune in the ARISS contacts. Then their RTL-SDR dongle could then actually be retuned to hear the contact. Just an idea...
Bob, WB4APR
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Dani EA4GPZ Sent: Saturday, October 15, 2016 7:36 AM To: amsat-bb@amsat.org Subject: Re: [amsat-bb] New Outernet L-Band service...
I hope someday a service like this will be available from an AMSAT geostationary service.
I'm pretty confident that the guys at AMSAT-DL are capable of doing this much better on the upcoming EsHail'2 than what Outernet is currently doing on Inmarsat...
They already have in mind a "DVB-S beacon"... broadcast from the ground station at Qatar ... carrying videos about Ham radio and Ham radio events on this signal.
What is more, if you have equipment to operate EsHail'2 on SSB, it's more or less easy to use either the narrowband transponder or the wideband transponder to transmit an Outernet-type signal through EsHail'2, so anyone can have a go with this.
Outernet uses 4200baud BPSK and half of the bitrate is spent for FEC. You can use a bit less bitrate to get a signal that will even pass through a conventional 2.7kHz SSB filter and you can use less bits for FEC to get increased data throughput (but more SNR required).
Dani EA4GPZ.
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sorry Daniel,
I believe you are missing the point. First of all, Outernet is a very interesting platform to experiment and their very inexpensive patch antenna, SDR based approach and software has already met lots of expectations. There is absolutely nothing wrong with changing hardware and no it is NOT obsolete! I still use my "old" Outernet antenna, sdr receiver for experimentation and yes, I am looking forward to their next steps. After all, its a hobby for us!
73, Stefan VE4NSA
On Wed, Mar 14, 2018 at 8:40 PM, Daniel Cussen dan@post.com wrote:
I noticed another news story from Outernet and I have some comments.
For those who don't know Outernet is a "commercial" /for the greater good, satellite downlink only service providing low bandwidth data, aimed at filling and updating a hard drive with news and info, aimed at developing nations, a free to receive data stream, for educational purposes etc. Their latest stunt/change is to downlink on 12Ghz from a Geostationary satellite, with reception without using a satellite dish, but instead just a bare LNB pointed in the direction of the geostationary satellite, using the gain of the horn inside the LNB.
News stories here: https://hackaday.com/2018/02/22/at-71572-km-you-wont-beat- this-lora-record/
https://store.outernet.is/blogs/the-official-outernet-blog/world-record
https://www.indiegogo.com/projects/lantern-a-global-satellite-data-radio
I would hesitate to recommend this system, as it is vapour-ware at the moment, and all the previous kits/hardware released have been dropped and made obsolete by changes to the broadcast. Previous broadcasts were 12Ghz geostationary, but decoded using a DVB-S tuner demodulator, then they changed to L-band low earth orbit immarsat and now they are back on geostationary, this time with a new modulation scheme making pointing easier. They are using the "LoRa" standard, basically just using a protocol that allows low signal margin decoding ( Chirp Spread Spectrum modulation (CSS) which trades data rate for sensitivity within a fixed channel bandwidth. ), similar to WSJT/PSK31 and other low data rate weak signal modes.
It is interesting they thing that a bare LNB (about 80 degree beam width) that seems to be doing the trick, although they also show pictures of patch antennas which presumably are designed for narrower beam width more suited to this.
The main caution I would have is they seem to be constantly peddling hardware, which soon becomes obsolete, without in fact any real business model to fund the venture. They claim their business model will be advertising or donations, obtained after the system catches on, on a large scale, but I have not seen any real attempt to get wide scale adoption in poor regions. They either do not have the funds or cannot get critical adoption for this one-way solution. Anyway I would encourage Amateurs to look at the "technology demonstration" they have made and consider if similar techniques could be applied to LEO or Geostationary Amateur or Emergency uses. Assuming they are still relaying the weekly AMSAT news (I have not seen any actual listing of what is actually downlinked, except for vague references to tests and some of Wikipedia) it might be a good fun project, but beware the technology is very untested and if (or when) they go bust, then the signals will stop. I have to wonder if the L-band service was a short term contract, that they can no longer pay for, and that they have fallen back to cheaper geostationary data.
If someone could set up a receiver (when they actually re-launch/start a new service) and list what is actually down linked, that would be good to know, but for now I would consider it still very much in the testing phase.
I would have thought if they were serious they would have launched a finished tested solution by now, aimed at developing nations and have it backed by advertising to make broadcasting self funding.
Dan EI9FHB
On 24/10/2016, Robert Bruninga bruninga@usna.edu wrote:
The Outernet L-band feed is now carrying a condensed version of the AMSAT and ARISS weekly news files. (Global Geosat coverage except for Northern Alaska)...
Receivers are simple: http://aprs.org/outnet.html
For ARISS, I manually added a 2 char grid square to each school listed in the school schedule and am asking the outernet folks to parse out that location info and plot a 1200 km footprint on their weather globe showing where people can tune in the ARISS contacts. Then their RTL-SDR dongle could then actually be retuned to hear the contact. Just an idea...
Bob, WB4APR
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Dani EA4GPZ Sent: Saturday, October 15, 2016 7:36 AM To: amsat-bb@amsat.org Subject: Re: [amsat-bb] New Outernet L-Band service...
I hope someday a service like this will be available from an AMSAT geostationary service.
I'm pretty confident that the guys at AMSAT-DL are capable of doing this much better on the upcoming EsHail'2 than what Outernet is currently doing on Inmarsat...
They already have in mind a "DVB-S beacon"... broadcast from the ground station at Qatar ... carrying videos about Ham radio and Ham radio events on this signal.
What is more, if you have equipment to operate EsHail'2 on SSB, it's more or less easy to use either the narrowband transponder or the wideband transponder to transmit an Outernet-type signal through EsHail'2, so anyone can have a go with this.
Outernet uses 4200baud BPSK and half of the bitrate is spent for FEC. You can use a bit less bitrate to get a signal that will even pass through a conventional 2.7kHz SSB filter and you can use less bits for FEC to get increased data throughput (but more SNR required).
Dani EA4GPZ.
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions
expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
also INMARSAT is an L-band GEO system, not LEO
Howie AB2S
________________________________ From: AMSAT-BB amsat-bb-bounces@amsat.org on behalf of Stefan Wagener wageners@gmail.com Sent: Wednesday, March 14, 2018 4:34 PM To: Daniel Cussen Cc: AMSAT BB Subject: Re: [amsat-bb] Outernet L-Band now carries AMSAT and ARISS weekly bulletins
Sorry Daniel,
I believe you are missing the point. First of all, Outernet is a very interesting platform to experiment and their very inexpensive patch antenna, SDR based approach and software has already met lots of expectations. There is absolutely nothing wrong with changing hardware and no it is NOT obsolete! I still use my "old" Outernet antenna, sdr receiver for experimentation and yes, I am looking forward to their next steps. After all, its a hobby for us!
73, Stefan VE4NSA
On Wed, Mar 14, 2018 at 8:40 PM, Daniel Cussen dan@post.com wrote:
I noticed another news story from Outernet and I have some comments.
For those who don't know Outernet is a "commercial" /for the greater good, satellite downlink only service providing low bandwidth data, aimed at filling and updating a hard drive with news and info, aimed at developing nations, a free to receive data stream, for educational purposes etc. Their latest stunt/change is to downlink on 12Ghz from a Geostationary satellite, with reception without using a satellite dish, but instead just a bare LNB pointed in the direction of the geostationary satellite, using the gain of the horn inside the LNB.
News stories here: https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fhackaday.c... this-lora-record/
https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fstore.oute...
https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.indieg...
I would hesitate to recommend this system, as it is vapour-ware at the moment, and all the previous kits/hardware released have been dropped and made obsolete by changes to the broadcast. Previous broadcasts were 12Ghz geostationary, but decoded using a DVB-S tuner demodulator, then they changed to L-band low earth orbit immarsat and now they are back on geostationary, this time with a new modulation scheme making pointing easier. They are using the "LoRa" standard, basically just using a protocol that allows low signal margin decoding ( Chirp Spread Spectrum modulation (CSS) which trades data rate for sensitivity within a fixed channel bandwidth. ), similar to WSJT/PSK31 and other low data rate weak signal modes.
It is interesting they thing that a bare LNB (about 80 degree beam width) that seems to be doing the trick, although they also show pictures of patch antennas which presumably are designed for narrower beam width more suited to this.
The main caution I would have is they seem to be constantly peddling hardware, which soon becomes obsolete, without in fact any real business model to fund the venture. They claim their business model will be advertising or donations, obtained after the system catches on, on a large scale, but I have not seen any real attempt to get wide scale adoption in poor regions. They either do not have the funds or cannot get critical adoption for this one-way solution. Anyway I would encourage Amateurs to look at the "technology demonstration" they have made and consider if similar techniques could be applied to LEO or Geostationary Amateur or Emergency uses. Assuming they are still relaying the weekly AMSAT news (I have not seen any actual listing of what is actually downlinked, except for vague references to tests and some of Wikipedia) it might be a good fun project, but beware the technology is very untested and if (or when) they go bust, then the signals will stop. I have to wonder if the L-band service was a short term contract, that they can no longer pay for, and that they have fallen back to cheaper geostationary data.
If someone could set up a receiver (when they actually re-launch/start a new service) and list what is actually down linked, that would be good to know, but for now I would consider it still very much in the testing phase.
I would have thought if they were serious they would have launched a finished tested solution by now, aimed at developing nations and have it backed by advertising to make broadcasting self funding.
Dan EI9FHB
On 24/10/2016, Robert Bruninga bruninga@usna.edu wrote:
The Outernet L-band feed is now carrying a condensed version of the AMSAT and ARISS weekly news files. (Global Geosat coverage except for Northern Alaska)...
Receivers are simple: https://eur03.safelinks.protection.outlook.com/?url=http%3A%2F%2Faprs.org%2F...
For ARISS, I manually added a 2 char grid square to each school listed in the school schedule and am asking the outernet folks to parse out that location info and plot a 1200 km footprint on their weather globe showing where people can tune in the ARISS contacts. Then their RTL-SDR dongle could then actually be retuned to hear the contact. Just an idea...
Bob, WB4APR
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Dani EA4GPZ Sent: Saturday, October 15, 2016 7:36 AM To: amsat-bb@amsat.org Subject: Re: [amsat-bb] New Outernet L-Band service...
I hope someday a service like this will be available from an AMSAT geostationary service.
I'm pretty confident that the guys at AMSAT-DL are capable of doing this much better on the upcoming EsHail'2 than what Outernet is currently doing on Inmarsat...
They already have in mind a "DVB-S beacon"... broadcast from the ground station at Qatar ... carrying videos about Ham radio and Ham radio events on this signal.
What is more, if you have equipment to operate EsHail'2 on SSB, it's more or less easy to use either the narrowband transponder or the wideband transponder to transmit an Outernet-type signal through EsHail'2, so anyone can have a go with this.
Outernet uses 4200baud BPSK and half of the bitrate is spent for FEC. You can use a bit less bitrate to get a signal that will even pass through a conventional 2.7kHz SSB filter and you can use less bits for FEC to get increased data throughput (but more SNR required).
Dani EA4GPZ.
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions
expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: https://eur03.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.amsat.o...
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://eur03.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.amsat.o...
_______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://eur03.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.amsat.o...
Outernet just seems to be lacking in purpose. Experimentation is great. This group has spent quite a bit of money on leased transponder time and just burned through it. Frankly I haven't been impressed with them. I would be far more likely to support AMSAT financially first in the future rather than some software developers who think that because they understand some bits of software development they therefore understand the world.
"Shifting Paradigms Without a Clutch" is the bumper sticker history of the project so far as I've observed.
Stephen Michael Kellat KC8BFI
On Wed, Mar 14, 2018 at 09:34:36PM +0100, Stefan Wagener wrote:
Sorry Daniel,
I believe you are missing the point. First of all, Outernet is a very interesting platform to experiment and their very inexpensive patch antenna, SDR based approach and software has already met lots of expectations. There is absolutely nothing wrong with changing hardware and no it is NOT obsolete! I still use my "old" Outernet antenna, sdr receiver for experimentation and yes, I am looking forward to their next steps. After all, its a hobby for us!
73, Stefan VE4NSA
On Wed, Mar 14, 2018 at 8:40 PM, Daniel Cussen dan@post.com wrote:
I noticed another news story from Outernet and I have some comments.
For those who don't know Outernet is a "commercial" /for the greater good, satellite downlink only service providing low bandwidth data, aimed at filling and updating a hard drive with news and info, aimed at developing nations, a free to receive data stream, for educational purposes etc. Their latest stunt/change is to downlink on 12Ghz from a Geostationary satellite, with reception without using a satellite dish, but instead just a bare LNB pointed in the direction of the geostationary satellite, using the gain of the horn inside the LNB.
News stories here: https://hackaday.com/2018/02/22/at-71572-km-you-wont-beat- this-lora-record/
https://store.outernet.is/blogs/the-official-outernet-blog/world-record
https://www.indiegogo.com/projects/lantern-a-global-satellite-data-radio
I would hesitate to recommend this system, as it is vapour-ware at the moment, and all the previous kits/hardware released have been dropped and made obsolete by changes to the broadcast. Previous broadcasts were 12Ghz geostationary, but decoded using a DVB-S tuner demodulator, then they changed to L-band low earth orbit immarsat and now they are back on geostationary, this time with a new modulation scheme making pointing easier. They are using the "LoRa" standard, basically just using a protocol that allows low signal margin decoding ( Chirp Spread Spectrum modulation (CSS) which trades data rate for sensitivity within a fixed channel bandwidth. ), similar to WSJT/PSK31 and other low data rate weak signal modes.
It is interesting they thing that a bare LNB (about 80 degree beam width) that seems to be doing the trick, although they also show pictures of patch antennas which presumably are designed for narrower beam width more suited to this.
The main caution I would have is they seem to be constantly peddling hardware, which soon becomes obsolete, without in fact any real business model to fund the venture. They claim their business model will be advertising or donations, obtained after the system catches on, on a large scale, but I have not seen any real attempt to get wide scale adoption in poor regions. They either do not have the funds or cannot get critical adoption for this one-way solution. Anyway I would encourage Amateurs to look at the "technology demonstration" they have made and consider if similar techniques could be applied to LEO or Geostationary Amateur or Emergency uses. Assuming they are still relaying the weekly AMSAT news (I have not seen any actual listing of what is actually downlinked, except for vague references to tests and some of Wikipedia) it might be a good fun project, but beware the technology is very untested and if (or when) they go bust, then the signals will stop. I have to wonder if the L-band service was a short term contract, that they can no longer pay for, and that they have fallen back to cheaper geostationary data.
If someone could set up a receiver (when they actually re-launch/start a new service) and list what is actually down linked, that would be good to know, but for now I would consider it still very much in the testing phase.
I would have thought if they were serious they would have launched a finished tested solution by now, aimed at developing nations and have it backed by advertising to make broadcasting self funding.
Dan EI9FHB
On 24/10/2016, Robert Bruninga bruninga@usna.edu wrote:
The Outernet L-band feed is now carrying a condensed version of the AMSAT and ARISS weekly news files. (Global Geosat coverage except for Northern Alaska)...
Receivers are simple: http://aprs.org/outnet.html
For ARISS, I manually added a 2 char grid square to each school listed in the school schedule and am asking the outernet folks to parse out that location info and plot a 1200 km footprint on their weather globe showing where people can tune in the ARISS contacts. Then their RTL-SDR dongle could then actually be retuned to hear the contact. Just an idea...
Bob, WB4APR
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Dani EA4GPZ Sent: Saturday, October 15, 2016 7:36 AM To: amsat-bb@amsat.org Subject: Re: [amsat-bb] New Outernet L-Band service...
I hope someday a service like this will be available from an AMSAT geostationary service.
I'm pretty confident that the guys at AMSAT-DL are capable of doing this much better on the upcoming EsHail'2 than what Outernet is currently doing on Inmarsat...
They already have in mind a "DVB-S beacon"... broadcast from the ground station at Qatar ... carrying videos about Ham radio and Ham radio events on this signal.
What is more, if you have equipment to operate EsHail'2 on SSB, it's more or less easy to use either the narrowband transponder or the wideband transponder to transmit an Outernet-type signal through EsHail'2, so anyone can have a go with this.
Outernet uses 4200baud BPSK and half of the bitrate is spent for FEC. You can use a bit less bitrate to get a signal that will even pass through a conventional 2.7kHz SSB filter and you can use less bits for FEC to get increased data throughput (but more SNR required).
Dani EA4GPZ.
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions
expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
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El 14/03/18 a las 20:40, Daniel Cussen escribió:
I would hesitate to recommend this system, as it is vapour-ware at the moment, and all the previous kits/hardware released have been dropped and made obsolete by changes to the broadcast. Previous broadcasts were 12Ghz geostationary, but decoded using a DVB-S tuner demodulator, then they changed to L-band low earth orbit immarsat and now they are back on geostationary, this time with a new modulation scheme making pointing easier. They are using the "LoRa" standard, basically just using a protocol that allows low signal margin decoding ( Chirp Spread Spectrum modulation (CSS) which trades data rate for sensitivity within a fixed channel bandwidth. ), similar to WSJT/PSK31 and other low data rate weak signal modes.
It is interesting they thing that a bare LNB (about 80 degree beam width) that seems to be doing the trick, although they also show pictures of patch antennas which presumably are designed for narrower beam width more suited to this.
Hi Daniel,
I also find it a bit hard to believe that the current Outernet goal can be made to work: a 30kbps stream from a GEO Ku-band satellite that can be received with a bare LNB or small patch antenna. This is not necessarily impossible if you run the numbers, but its feasibility is pretty borderline. I'll believe it when I see it working.
As I understand, one of the main issues they're having is co-channel interference. This goes as follows: if you look at link budget alone (free space path loss, the gain of an LNB and so on), maybe things can look OK. However, in the real world what happens is that your LNB has a wide beam, so you receive the signals from over a dozen different GEO satellites. The signal you want to receive is now interfered by DVB-S transponders (or other signals) from many different satellites and now you have a problem (as before the main contribution of noise was the LNB noise figure, and now you notice that the noise floor is much higher due to interference).
This is not a problem when using a dish, since the beamwidth is rather narrow and your dish only sees a few satellites at a time, so interference is unlikely. But when you look at many satellites instead, the spectrum is extremely crowded.
The fun thing about this story is that they claim that the are experimenting with LoRA to fight co-channel interference (since LoRA is spread spectrum). In my last talk about Outernet I commented that this is nonsense and that they don't understand properly how spread spectrum works.
If you think about it, spread spectrum (in comparison to a narrowband signal) works very well against narrowband interference, but it doesn't make any difference against wideband interference. In this case, the co-channel interference is DVB-S and other wideband signals. For all practical effects, they just look as an elevated noise floor and there is no way to fight against them, spread spectrum or not.
Since the Outernet topic has come to this mailing list once again, I take the liberty to remind you that while Outernet can be interesting from the technical point of view, they have always kept secret their modulation, coding, protocols and so on, and the key parts of the receiver are closed-source. This is no good for Amateur Radio and experimentation in general.
Thanks to my work and the help of some other people, now there is a fully open-source receiver for the (now defunct) L-band signal, as well as public specifications for everything. This was done by reverse engineering, without any support from the Outernet team (which don't seem to like this open-source receiver).
Some references:
https://github.com/daniestevez/free-outernet
http://destevez.net/tag/outernet/
73,
Dani EA4GPZ.
participants (7)
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Dani EA4GPZ -
Daniel Cussen -
Howie DeFelice -
Robert Bruninga -
Scott -
Stefan Wagener -
Stephen Michael Kellat