I have recently been to FAB and most of those planes coming in are MLAT planes, I know there is PPmobile, FR24, Flight Aware, Plane Finder but could be ultimate ADS-B Exchange app for spotting outside the code is not maintained any more, but it's open source app for android: It could be forked and used in terrain to increase coverage and help us plane spotting? I have installed the app on my SM-T825 and it works perfectly, but no MLAT just local ADS-B .. I know I could always take Laptop with SDR dongle, but most people already have tablet and its smaller than laptop when driving/going around the perimeter fence tablet does not look so suspicious
githubDOTcom/flightaware/adsb-flight-scanner-android Is the home of the app = Open Source ADS-B aircraft position tracker on the 1090 MHz (ES) and 978 MHz (UAT) bands for Android devices
Looks overcomplicated for 90% of users. Better take Pi to your car, use car charger for Pi and your mobile device in WiFi router mode (only if you want to try remote location). There is nothing like ADSBx MLAT client for Android so you can't feed. Maybe idea is not bad but doesn't bring a lot.
Yes, but how about exact GPS that you need for the MLAT to work? I have been think about this, tried even pi-topDOTcom/products/pi-top but still needed GPS .... On the other hand, tablet already has GPS some have more GLONAS etc. .... so I think perfect for this kind of job. Plus if you have Wi-Fi+LTE version it's all in one device, plus possibly long battery live as well. What would you do, when you need to leave car parked away from airfield as no access? RPi is brilliant, but for static use ...
You are absolutely right, but when you leave your car you are usually taking your mobile devices with you . About GPS, do you know any feeder which is continouosly checking your coordinates? I don't.
https://www.openflightsolutions.com/ http://www.stratux.co/ Those perhaps could be turned into ADS-B Exchange feeders, have GPS, but the cost of 240 USD against Tablet that you can use for other stuff with 10 USD dongle .......
Any feeder have to log in reporting its position, every position change should cause disconnect and connect again. ADSBx servers have limited capability, time to reconnect can take a lot. As I wrote, idea is not bad but it will take long time to modify websites code. At the moment for me this is something like interesting curiosity.. But who knows, maybe in the future...
Fair point, but the LTE networks are getting better with lower latency/jitter. The main reason FlightAware discontinued the app was that they got loots of RaspPi users, but I think there is a use for it, I used it to feed data in when out and about. There is no better way to get MLAT working better than from those in field This could be the perfect tool for all those who like aviation (plane spotters etc.) DO you know by any chance how big is the community around ADS-B Exchange? The app could be free for those who already contribute to ADS-B Exchange and paid for those who do not feed the data....
MLAT is extended to 2020. Main problem is how to treat signal from mobile station if it is not reporting actual position (position data are send only during logon). Next point, signal strength is used to evaluate distance (do you think that signal from car driving with speed ca. 90km/h is reliable source?). ADSBx community is incomparable to FR24 or FA but there are more than 1000 feeders (never tried to count stations from sync matrix).
I am talking about walking around the airport (sort of stationary), where you spotting, waiting for someone to pickup just returning from trip (stationary mainly), if you are working at the airport, you park your car near by (at least we do at LHR) ..... driving 40(30)mph around the airport would not make sense for MLAT, but see live stats as we are used at home would be cool and they (FA) had it working on that app, just add MLAT
Please do not compare FA (strictly commercial, earning a lot of money) to ADSBx (coop of volunteers). As I wrote, this app is interesting but at the moment doesn't bring a lot to this website.
How many people of us you think are working in airports? Maybe some... If you are python/debian expert please rewrite this app.
Walking around isn't going to throw off MLAT calculations from a Pi feeder - it's not the important that coordinates are down to the millimeter. RF travels at speed of light, a even a mile here and there is within margin of error. Bigger issues is making sure cPi locks stay synced with NTP. I'm going to build one for Oshkosh next year that will run from a solar panel / battery in my backpack. We have around 2000+ feeders live at any one time, and we have most of the western world covered and we're working on the rest. FA has about 13000 or so, they also broker data with Aireon to stabilize decoding in busy air spaces. Not sure about FR24, but assuming they have the same business model of getting people to setup feeders and selling the data/analytics/tracking. You can't compare ADSBx to FA or FR24, ADSBx isn't a commercial business deriving profits from reselling feeder data with 100+ employees and a full sales staff. ADSBx shares all the data back to the community as much as we can reasonably do.. ADSBx doesn't take money to block aircraft, filter aircraft, and sell the fleet tracking. FR24 and FA do nothing for anyone but themselves. People do like having pointless dashboard summaries on the internet, something we need a lot of work to create to placate the masses. If you want live stats look at your local feeder? ADSBx image has a massive configurable dashboard that costs ADSBx no bandwidth and no server costs. Why the need to go to adsbexchange.com and see stats that require more server expense and time to maintain? I'm all for it if someone wants to take the torch and write the code.
Chris and the guys working on stratux are nice and have helped ADSBx with some server and programming. They are also volunteers but they have made a business out of selling the hardware. reddit.com/r/stratux stratux.me I thought about assembling feeders for ADSBx but I would have to charge $250+ to make it worth the time to buy the hardware, test, assemble, and then of course people will have problems and hardware will fail occasionally - then they will get angry and expect ADSBX to warranty it or replace. To keep my sanity it's best to provide and shopping list and turn them loose on it!
MLAT working is a more about having the CPU power to MLAT the feeders data. We run an expensive 5Ghz gaming server that hosts the MLAT instances and CPU is always pegged 100%. FA has prevented Oliver (mutability) (dump1090 fork) from working on any opensource code that competes with FlightAware, so if there is anyone to blame for the lack further development of ADS-B tools - you can point directly at FA and it's founder. If FA had it's way ADSBx would be closed down as soon as possible. We reluctantly want to spend time, effort, and money on more MLAT processing servers when it's gone in 2 years anyway.
PS I have GPS working on the ADSBx image. The code to somehow restart dump1090 periodically with new lat/lon is needed to be written. But like I said .. even a few miles isn't important - more important is time sync with NTP. RF is speed of light. 300,000 kilometers a second. 300,000,000 meters/second. Theoretically they have an infinite range, but since they lose energy as the inverse square of the distance traveled, they become very weak quickly and are drowned out by more energetic local sources. Hence the need for FA to sell feeder data to Aireon in busy airspace. Walking around an airshow with GPS configured to the center of the field isn't going to make a lick of difference.
I am greatly interested into this "mobile" receiver... This is actually in my plans to play around with this idea (the gps antenna is right on my workbench right now beside a PI3B+). I now just need time to properly analyze how dump1090 works and how it could be possible to inject GPSd coordinates into it OR use the raw output to inject the coordinates into the feed and pass to whatever software needs it. To keep time more constant, despite possible poor/dead network, I think one might consider using an hardware clock to the pi (https://thepihut.com/blogs/raspberr...adding-a-real-time-clock-to-your-raspberry-pi). NTP would set this clock when network is fast enough on regular basis otherwise the pi would use the hardware clock alone... I keep this project for winter
Not possible. lat/lon are passed on execution. dump1090 really doesn't need your lat/lon but mlat does. So you set max-range to 1500 nm and put a relative gps position. Or you restart it based on some delta or time - every x restart dump with new GPS.
so partly rewriting dump1090 to have it monitor GPSD coordinates every X seconds (1sec may be something to start with) and use those on reception might be an option ?
