A $20 RTL-SDR tracks aircraft over your city. Just add some free software and have some fun. You can see commercial flights land, take off or just pass by.
Most aircraft emit Automated Dependent Surveillance – Broadcast. ADS-B automatically broadcasts data to enable aircraft surveillance or tracking. In Canada, it is used for air traffic control. Aircraft identification, current position, altitude, and velocity are among the data provided every few seconds. Commercial airliners broadcast at the microwave frequency of 1090 MHz. In many ways, ADS-B is more accurate and cheaper than radar. Position information comes from the plane’s navigation system and GPS.
Now, here’s the neat part. ADS-B is not encrypted. Anyone with a microwave receiver can pick up the signal. So, it turns out that it is very easy for me to display all of the aircraft over Calgary on my computer. I can see aircraft taking off, landing or just flying by. I can see its call sign, flight altitude, rate of descent or ascent, bearing and speed.
Three aircraft coming in for landing at YYC, and one just flying past at 36,000 feet in the picture above. This was on a quiet Saturday evening.
If you want to listen to the tower communications with aircraft while you watch, head on over to LiveATC and do a search for your airport. This will stream ATC radio to your computer.
RTL-SDR Tracks Aircraft for $20 – DIY
RTL-SDR is a little USB stick that contains a full-fledged radio receiver. It costs around $20 and comes with its own small antenna. My friend Bob gave me one for Christmas two years ago. Frequency coverage is approximately 28 to 1750 MHz. So, it covers the ADS-B frequency of 1090 MHz. Just add some free software.
The easiest way to set up is to download the RTL1090 software from Germany. The installation guides you through the basic setup, including drivers for your RTL-SDR dongle. Then, you just run the software. There are two parts to the operation. First, the software builds a list of ADS-B signals it hears. Second, if you have the latest update of RTL1090, you get to watch a graphic display. I am going to look around for some better display software which will show the aircraft movements on an actual map.
The normal RTL-SDR antenna is very small, just a few inches long. Make sure you set up the RTL-SDR on a computer on the second floor of your house, if possible, for stronger signals. Avoid the basement. Or, use a better antenna. Still, I am at the opposite end of town from the airport. This simple setup in the main floor den works fine.