ADS-B

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cartman
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Re: ADS-B

Post by cartman » Thu Oct 27, 2011 4:12 pm

In addition to flightradar24.com I have discovered that you get Australian traffic as well on http://planefinder.net/

There are variations on what is shown depending who is feeding what site and where they are located.


Grant
Professional Scanner nut. Ibis bin chicken of radio scraps
Scanners:
Uniden 325P2, Whistler TRX-1, GRE PSR800 x 2, Uniden 780 x 3, Uniden 796, Uniden 396 x 2, Uniden 246,
Software:
DSD v2.368, Unitrunker, Trunkview

Longreach
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Re: ADS-B

Post by Longreach » Thu Oct 27, 2011 5:36 pm

planefinder is available too as an iphone app.
cheers
Matt
VK2MRC

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cartman
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Re: ADS-B

Post by cartman » Wed Nov 02, 2011 7:20 am

Fascinating paper released for the general public on the military's concerns with ADS-B
http://dodreports.com/pdf/ada545599.pdf

Elsewhere I found reference to an encrypted enhanced version known as Mode 5 Level 1 or Level 2 to deal with various concerns
http://www.mcgraw-hillhomelandsecurity. ... 0Storm.pdf


Grant
Professional Scanner nut. Ibis bin chicken of radio scraps
Scanners:
Uniden 325P2, Whistler TRX-1, GRE PSR800 x 2, Uniden 780 x 3, Uniden 796, Uniden 396 x 2, Uniden 246,
Software:
DSD v2.368, Unitrunker, Trunkview

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cartman
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Location: Liverpool, NSW, Australia

Re: ADS-B

Post by cartman » Sun Nov 06, 2011 4:59 am

I was trying to get my head around the various modes in use in ADS-B.
This is summarised from wikipedia's article on ADS-B
There are also some very good articles on Australian air traffic control etc in the November copy of "Australian Aviation"

Grant

Modes
Mode 1 – provides 2-digit 5-bit mission code. (military only – cockpit selectable)
Mode 2 – provides 4-digit octal unit code. (military only – set on ground for fighters, can be changed in flight by transport aircraft)
Mode 3/A – provides a 4-digit octal identification code for the aircraft, assigned by the air traffic controller. (military and civilian)
Mode 4 – provides a 3-pulse reply to crypto coded challenge. (military only)
Mode 5 – provides a cryptographically secured version of Mode S and ADS-B GPS position. (military only)
Mode 5 is divided into two levels.
Both are crypto-secure with Enhanced encryption, Spread Spectrum Modulation, and Time of Day Authentication.
Level 1 is similar to Mode 4 information but enhanced with an Aircraft Unique PIN.
Level 2 is the same as Mode 5 level one but includes additional information such as Aircraft Position and Other Attributes.
Mode C – provides 4-digit octal code for aircraft's pressure altitude. (military and civilian)
Mode S – provides multiple information formats to a selective interrogation.
Typically aircraft are assigned a unique 24-bit Mode S address.
The Mode S address is partitioned and a group of address ranges are allocated to each country.
Some counties change the assigned address for security reasons, and thus it might not be a unique address. (military and civilian)


Method of operation
Modes 1, 2, 4 and 5 are for military use only.
Modes 1, 2 and 3 are collectively known as Selective Identification Feature (SIF) modes.
Civilian aircraft use modes A, C and S.
Mode C which includes barometric pressure altitude information is often used in conjunction with mode A.
Mode A is often referred to as mode 3/A due to the similarity to the military mode 3.
Mode S is a new civilian mode developed to replace both mode A and C.
Professional Scanner nut. Ibis bin chicken of radio scraps
Scanners:
Uniden 325P2, Whistler TRX-1, GRE PSR800 x 2, Uniden 780 x 3, Uniden 796, Uniden 396 x 2, Uniden 246,
Software:
DSD v2.368, Unitrunker, Trunkview

citabria
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Re: ADS-B

Post by citabria » Thu Nov 24, 2011 12:58 pm

citabria wrote:Geoff,

Just out of interest there has been some experimental work in decoding transponders using the GNUradio/USRP framework - looks like its quite do-able for someone with the right coding skills..

http://sites.google.com/site/radiorausch/AvTrans.html

Cheers,
Matt
2 years later, and a good mate of mine has made this little idea a reality. It was presented at RUXCON 2011, and heres the video --> http://www.youtube.com/watch?v=Vn-dpUegUDQ

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cartman
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Re: ADS-B - Updated links

Post by cartman » Mon Jan 09, 2012 5:26 pm

Last edited by cartman on Mon Feb 10, 2020 10:06 pm, edited 3 times in total.
Professional Scanner nut. Ibis bin chicken of radio scraps
Scanners:
Uniden 325P2, Whistler TRX-1, GRE PSR800 x 2, Uniden 780 x 3, Uniden 796, Uniden 396 x 2, Uniden 246,
Software:
DSD v2.368, Unitrunker, Trunkview

Farsouthscanner
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Joined: Thu Sep 04, 2008 10:47 pm
Location: Far South Coast NSW

Re: ADS-B

Post by Farsouthscanner » Tue Oct 30, 2012 8:32 pm

I am thinking of getting an ADS-B receiver, maybe for Christmas.
I don't want to spend a lot of money so I was looking at this one
http://46.40.125.13:8000/ I would like to share my data on Flightradar24 as I have found that I can see REX planes leaving Sydney but they disappear around Ulladulla, I am thinking that this is because they fly lower and are in the current providers dead spots. Does this sound right?
Anyway I would have to get something like the above receiver and another multicoupler to plug into my existing one as I am using all the ports on it already. This would be connected to my Icom A7000 discone. Would this be a good setup and how far away could I receive, the discone has free line of site to the horizon to the east.
Thanks for any info
Mark

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cartman
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Re: ADS-B

Post by cartman » Tue Nov 20, 2012 12:01 pm

While waiting for a friends plane ADS-B signal to appear at Sydney Airport enroute to Tasmania on "flightradar24.com" and "planefinder.net" I noticed that ground vehicles appear to have their own hex id on ADS-B.
I saw Fire 9 come up on the screen.
A little bit of googling reveals that the following ids are ground vehicles at Sydney Airport.
So in addition to monitoring the airport fire services on 500Mhz, the GRN x-band link on FRNSW talkgroup 10111, it would seem that you can see them on ADS-B as well.
Has anybody been compiling Hex ID lists?
I have started a little while ago and update it on occasions


Grant


7CF782 SOVSM 2 RADAR
7CF7BC
7CF7BD
7CF7BE
7CF7C0 TEST1234
7CF7C1 TEST1234
7CF7C2 TEST1234
7CF7C3 TEST1234
7CF3CA "SSM1"
7CF3CB "SSM2"
7CF3CC Fire 2
7CF3CD Fire 4 "SSM4"
7CF3C7 Fire 7
7CF3C8
7CF3C9 Fire 9
Professional Scanner nut. Ibis bin chicken of radio scraps
Scanners:
Uniden 325P2, Whistler TRX-1, GRE PSR800 x 2, Uniden 780 x 3, Uniden 796, Uniden 396 x 2, Uniden 246,
Software:
DSD v2.368, Unitrunker, Trunkview

Farsouthscanner
Posts: 431
Joined: Thu Sep 04, 2008 10:47 pm
Location: Far South Coast NSW

Re: ADS-B

Post by Farsouthscanner » Mon Nov 26, 2012 6:14 pm

Thanks for the info Grant.
My receiver arrived today and have just tried it out.
I received the Jetstar flight from Sydney to Hobart and an airforce plan going to Tasmania from Canberra.
I picked up the Jetstar flight around Moruya, about 125km to the north, the airforce plan was picked up just north of Bombala, about 60km west.
This is using my discone antenna set up that I am using for the rest of the scanners.
Mark

Wonky
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Re: ADS-B

Post by Wonky » Wed Nov 28, 2012 12:39 pm

Coming off a discone that reception range is pretty good. If you had a dedicated ADS B antenna that range would definately increase - I get about 180 NM range. I will try and dig up a link to the antenna I had shipped from the UK...

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