Questions about ads-b data acquisition

[TakeOffDream]

Hello friends, everyone. I recently noticed that some of the data uploaded using the equipment I built myself will have data such as the temperature outside the aircraft, wind speed at high altitude, Mach, ground speed, and so on. May I ask you how these data were obtained, thank you.

[Oblivian]

datasources.jpg

Some of the calculations when not provided by aircraft noted here
https://www.wmo.int/pages/prog/www/I...2(11)_Body.pdf

[TakeOffDream]

I'm sorry, because I am Chinese and my English is not very good. I used translation software to see the link you sent me. I would like to ask, if I want to upload the data such as Mach, temperature and ground speed of the aircraft near my location, what do I need to do? Thank you

[Oblivian]

I'm sorry, because I am Chinese and my English is not very good. I used translation software to see the link you sent me. I would like to ask, if I want to upload the data such as Mach, temperature and ground speed of the aircraft near my location, what do I need to do? Thank you

You can't send what you don't receive. And all that you do receive is sent.

Server calculates rest.

[TakeOffDream]

I understand a bit. You mean that the data such as Mach and temperature are calculated by the server. We ca n’t receive those data, right?

[Oblivian]

Some calculated from information it knows

Some receivers receive DF20 reply message from aircraft capable of sending. when ground station asks for it

If DF20/21 sent and your feeder can receive. It will upload:


BDS Register Content
1,0 Data link capability report Transponder capability
1,7 GICB capability report Supported Mode S registers
2,0 Aircraft identification Call-sign
3,0 ACAS active resolution advisory Resolution advisories
4,0 Selected vertical intention Selected altitude
Barometric pressure setting
4,4 Meteorological routine air report Wind speed
(MRAR) Wind direction
Static air temperature
Average static pressure
Humidity
5,0 Track and turn report Roll angle
True track angle
Ground speed
Track angle rate
True airspeed
6,0 Heading and speed report Magnetic heading
Indicated airspeed
Mach number
Vertical speed

If only altitude provided. MLAT work out position. 2 positions in known time = estimated speed.

http://woodair.net/sbs/article/bareb...ocket_data.htm

[wiedehopf]

Are you asking for it to be displayed on your local map?

Check out this: https://github.com/wiedehopf/adsb-sc...ion-for-readsb

Note this will modify your feeder quite a bit. No guarantees

[TakeOffDream]

Hello, this setting can display Mach, temperature data?

[wiedehopf]

It will show mach, not temperature though.

Some of this depends on the aircraft having the capability and the radar stations in your area interrogating the aircraft.

Not sure how exactly FR24 gets the temperature, maybe it's calculated from other data.