ADS-B stuff that I have found II
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UAT is the carrier, CDMA is the operating code.
UAT can carry multiple coding methodologies, and multiple service providers.
As asimple example the Weather carraige on UAT simultaneous with ADSB, it is not rocket science to multiplex on broad band capable carriers.
Yes UAT was around before 1090ES but Australia deemed it too expensive to set up the ground stations, we will rue the day that series of decisionswas made.
UAT can carry multiple coding methodologies, and multiple service providers.
As asimple example the Weather carraige on UAT simultaneous with ADSB, it is not rocket science to multiplex on broad band capable carriers.
Yes UAT was around before 1090ES but Australia deemed it too expensive to set up the ground stations, we will rue the day that series of decisionswas made.
Thread Starter
T28D very true. I do not have an argument against as to the capabilities of the various systems.
I remember a post on these threads many years ago from a lecturer( I think?) from Charles Darwin Uni that espoused the use of the terrestrial mobile network as the datalink for a navigation app that he was working on. I think I even posted against as to the expense of such a datalink. How wrong am I? I have used a couple of PC based apps that use the mobile network and using my current subs for my smartphone... And....after attending an Avidyne demo for their satellite link off the LEO networks??? I think the mobile network wins.
I remember a post on these threads many years ago from a lecturer( I think?) from Charles Darwin Uni that espoused the use of the terrestrial mobile network as the datalink for a navigation app that he was working on. I think I even posted against as to the expense of such a datalink. How wrong am I? I have used a couple of PC based apps that use the mobile network and using my current subs for my smartphone... And....after attending an Avidyne demo for their satellite link off the LEO networks??? I think the mobile network wins.
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I have often wondered what could be achieved using Digital Radio Mondiale - Wikipedia, the free encyclopedia as data link for WX and traffic, and at what cost compared to satellite (LEO or geo) or VHF/UHF systems. Just a couple of channels gives a fair amount of bandwidth.
but Australia deemed it too expensive to set up the ground stations,
And yet the ground stations Airservices is using are virtually identical to the ones used in US, just the "Australia" ground station does not have the UAT circuit board in, leaving a/the spare slot.
I am advised that the way the setup works, the signals from the ground station to the ATC computers are common, regardless of the transmission and reception between variously equipped aircraft and the ground station.
If this is correct, it means that we could have UAT, as well as 1090ES here, with all the advantages of the much cheaper UAT equipment.
However, this would need a major psychological shift away from ADS-B IN being regarded as the "poor man's TCAS" answer to a non-existent collision risk problem, something that seems highly unlikely.
FAA completely discount ADS-B for an aircraft to aircraft collision prevention function, for them it is an ATC tool, TCAS 11 will be with us for a very long time.
Tootle pip!!
PS: For info. about how limited 1090ES is, and how easily it is swamped, go looking for FAA/Mitre Corp, Google is your friend. This problem was raised more than twenty years ago, as a serious impediment to the long term use of the present transponder standard, the problem is not ADS-B ES specific, it applies to all operations of transponder modes C/S.
Last edited by LeadSled; 3rd Oct 2012 at 08:54.
Thread Starter
Yes, google IS your friend-
A study back in 2008 on exactly this very subject. Nice response as to possible outcomes. Still, reductions til 2015 then FRUIT increasing.
ASP report on 1030/1090 RF Development
Special note- INTEROPERABILITY
Acronym decode FRUIT-false replies unsynchronized to interrogator transmissions
Or- too many transponders keying over the top of each other.
A study back in 2008 on exactly this very subject. Nice response as to possible outcomes. Still, reductions til 2015 then FRUIT increasing.
ASP report on 1030/1090 RF Development
Special note- INTEROPERABILITY
Acronym decode FRUIT-false replies unsynchronized to interrogator transmissions
Or- too many transponders keying over the top of each other.
Last edited by OZBUSDRIVER; 4th Oct 2012 at 22:45.
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So it's easilly swamped?
You seem to have "form" on PPRune for pushing agendas far beyond your PPL flying capabilities.
You seem to have "form" on PPRune for pushing agendas far beyond your PPL flying capabilities.
OZ,
A good description of some of the problems resulting from the adoption of an outmoded system.
None of those issues arise with a modern broadband datalink, (be it UAT/CDMA or VDL/TDMA.instead of something dating back to WWII.
Tootle pip!!
A good description of some of the problems resulting from the adoption of an outmoded system.
None of those issues arise with a modern broadband datalink, (be it UAT/CDMA or VDL/TDMA.instead of something dating back to WWII.
Tootle pip!!
Thread Starter
FRUIT will only ever be a problem in the NE corridor in the US and parts of Europe. Personally? I would simply dream of a day when FRUIT becomes an issue here.
Plumbum!!!!! Why do you profer two separate systems for ATM. Incompatible unless AirServices put in low level rollout with an extraordinarily expensive broadband link to each ground station.... Unless you keep your old transponder.
INTEROPERABILITY! As much as I would appreciate the datalink there are far more cost effective means of supplying the data to the cockpit. UAT is the US version of VAN X works great but only in one state.
This is an old argument! Do you guys really want to go around again?
Plumbum!!!!! Why do you profer two separate systems for ATM. Incompatible unless AirServices put in low level rollout with an extraordinarily expensive broadband link to each ground station.... Unless you keep your old transponder.
INTEROPERABILITY! As much as I would appreciate the datalink there are far more cost effective means of supplying the data to the cockpit. UAT is the US version of VAN X works great but only in one state.
This is an old argument! Do you guys really want to go around again?
https://buy.garmin.com/shop/shop.do?pID=93601&ra=true
Folks,
Pity we don't have UAT.
Even if it is nice to have and not must have.
Who says the system requires an "extraordinarily expensive broadband datalink".
Maybe you should bone up on the FAA system. For the ADS-B part of the operation, the communications between the ground station and ATC computers is agnostic as to whether the aircraft/ground/aircraft part is 1090es OR UAT --- the bandwidth required is nothing special.
Don't confuse this part of the system with the bandwidth other service might use, everything from routine ATC traffic in lieu of VHF voice, through commercial non-ATC usage.
What I don't know about is how limited the bandwidth available is if a satellite has to be used in the loop, most of the FAA link between ADS-B ground stations and centers is terrestrial --- mostly the telephone network.
Tootle pip!!
Folks,
Pity we don't have UAT.
Even if it is nice to have and not must have.
Incompatible unless AirServices put in low level rollout with an extraordinarily expensive broadband link to each ground station
Maybe you should bone up on the FAA system. For the ADS-B part of the operation, the communications between the ground station and ATC computers is agnostic as to whether the aircraft/ground/aircraft part is 1090es OR UAT --- the bandwidth required is nothing special.
Don't confuse this part of the system with the bandwidth other service might use, everything from routine ATC traffic in lieu of VHF voice, through commercial non-ATC usage.
What I don't know about is how limited the bandwidth available is if a satellite has to be used in the loop, most of the FAA link between ADS-B ground stations and centers is terrestrial --- mostly the telephone network.
Tootle pip!!
Last edited by LeadSled; 5th Oct 2012 at 09:05.
Thread Starter
Unless I am very wrong. Whilst the boxes have spare racks in AirServices 1090es ground stations, the connection back to mummy is one way only. There is no facility to transmit FROM an ADS-B site. Purely passive system!
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Incompatible unless AirServices put in low level rollout with an extraordinarily expensive broadband link to each ground station....
Heck, even without the NBN birds, putting that capacity (and WAAS packages while we're at it*) on the Optus satellites that went up over the past decade would not have been "extraordinarily expensive".
That argument should be dead an buried.
* WAAS too was "extraordinarily expensive" because of the ground stations. Now we have the ground stations anyway (for ADS-B) and we still don't have WAAS. What a monumental cock-up.
Thread Starter
Baswell, love the way you think. 
(great minds
)
However, I think we all forget why AirServices went with 1090es in the first place....Radar replacement.... Imagine how much it would have cost to get 100% coverage ABV FL300 if they put in SSR heads. In effect, The cost of equipage has been transferred to the aircraft owner! The choice has been made for us by AirServices. The largest charged user, the airlines, would baulk at the idea of paying for a network that even smelt like a subsidy to GA....remember THAT argument? So, and enough of the politicking by myself for the first time on these two threads, 1090es is the equipment of choice in Australia and most all of the known world. UAT is site specific US and small parts of China around training facilities. We ain't going to be able to turn back that clock. UAT here is a waste without somebody else paying for the broadband content. Because! User pays on this puppy? Francis would have conniptions for the next century!
(great minds)However, I think we all forget why AirServices went with 1090es in the first place....Radar replacement.... Imagine how much it would have cost to get 100% coverage ABV FL300 if they put in SSR heads. In effect, The cost of equipage has been transferred to the aircraft owner! The choice has been made for us by AirServices. The largest charged user, the airlines, would baulk at the idea of paying for a network that even smelt like a subsidy to GA....remember THAT argument? So, and enough of the politicking by myself for the first time on these two threads, 1090es is the equipment of choice in Australia and most all of the known world. UAT is site specific US and small parts of China around training facilities. We ain't going to be able to turn back that clock. UAT here is a waste without somebody else paying for the broadband content. Because! User pays on this puppy? Francis would have conniptions for the next century!
Last edited by OZBUSDRIVER; 7th Oct 2012 at 10:14.
WAAS too was "extraordinarily expensive" because of the ground stations
The reason Airservices wasn't interested in WAAS, but LAAS, was that they couldn't charge for WAAS.
Tootle pip!!
Oz,
The FAA long since discounted ADS-B as other than a passive system, as far as collision avoidance is concerned and transponders must stay where TCAS is the go ---- but I am certain you know that they rebroadcast traffic information, UAT is always in and out. ADS-B as a component of TCAS is not going to happen any time soon.
Bas knows what he is talking about with available satellite bandwidth, we have come a long way since the original Inmarsat birds.
Even the cost of satellite based phone systems is dropping sharply, it is now about the same call cost as the original mobile phone of 20 years ago.
We are not going to see the benefits of modern technology re. ATS-B any time soon in Australia, thanks to the (as now very obvious) adoption of 1090ES as the high level system world wide.
Thanks a bunch, IATA/ATA and some N. American avionics manufacturers ---- as has all been detailed before.
Tootle pip!!
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, 1090es is the equipment of choice in Australia and most all of the known world. UAT is site specific US and small parts of China around training facilities.
Equipment of whose choice, I don't recall being asked for a vote on choice.
And arguably the 2 most trafficed nations on Earth U.S. and China have chosen UAT, now why might that be ???????
1090ES the VAN 5 of modern aviation data communication.
China is emerging as a major player in Aviation as its population would suggest it should.
On a different note the capacity of the transponders on the new NBN satellites wil be adequate to carry the data traffic for UAT, without any compromise to their primary function providing Broadband for remote communities.
Equipment of whose choice, I don't recall being asked for a vote on choice.
And arguably the 2 most trafficed nations on Earth U.S. and China have chosen UAT, now why might that be ???????
1090ES the VAN 5 of modern aviation data communication.
China is emerging as a major player in Aviation as its population would suggest it should.
On a different note the capacity of the transponders on the new NBN satellites wil be adequate to carry the data traffic for UAT, without any compromise to their primary function providing Broadband for remote communities.
Thread Starter
Gotta love these circular arguments....
T28D read what I wrote, cherry picking an argument? It's so you!
No matter which way you cut the cake, Plumbum, you still have the system chosen for you. When I first looked at this argument I was also hoping for UAT and WAAS for very selfish reasons. What "I" could get out of it. However, this is not the political argument.
Bas is quite correct. Affordable broadband is all around us now, both satellite and wireless terrestrial. If we want the goodies we have to put them in ourselves.
If there was one cabability that aviation was screaming out for, it was WAAS!
To think we have launched TWO geosynchronous birds since and rolled out no less than 28 stations linked....for a few cents more... And for national benefit? That does suck the big one!
T28D read what I wrote, cherry picking an argument? It's so you!
No matter which way you cut the cake, Plumbum, you still have the system chosen for you. When I first looked at this argument I was also hoping for UAT and WAAS for very selfish reasons. What "I" could get out of it. However, this is not the political argument.
Bas is quite correct. Affordable broadband is all around us now, both satellite and wireless terrestrial. If we want the goodies we have to put them in ourselves.
If there was one cabability that aviation was screaming out for, it was WAAS!
To think we have launched TWO geosynchronous birds since and rolled out no less than 28 stations linked....for a few cents more... And for national benefit? That does suck the big one!
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I really don't think this isbroadband !!!!!!!!!!!!!!!!!!!!!!!!!
FIS-B principally intended for GA aircraft
FIS-B for advisory use only (no guarantee of delivery)
not real time
not a substitute for airborne sensors, other alerting mechanisms
Key parameters:
update rate - 300 seconds
range limited to 40 to 80 nmi to ensure low altitude coverage
product mix (based on information available now):
1- (512 pixel x 512 pixel) graphical images
720 x 720 NM, 2 km resolution 50,000 bits
ATIS 2000
Windshear alerts
2000
PIREPS/Special Use Airspace (SUA) 1000
Total: 55,000 bits
(About 200 BPS delivered)
FIS-B principally intended for GA aircraft
FIS-B for advisory use only (no guarantee of delivery)
not real time
not a substitute for airborne sensors, other alerting mechanisms
Key parameters:
update rate - 300 seconds
range limited to 40 to 80 nmi to ensure low altitude coverage
product mix (based on information available now):
1- (512 pixel x 512 pixel) graphical images
720 x 720 NM, 2 km resolution 50,000 bits
ATIS 2000
Windshear alerts
2000
PIREPS/Special Use Airspace (SUA) 1000
Total: 55,000 bits
(About 200 BPS delivered)