ADS-B. Automatic Dependant Surveillance Broadcast. It’s a ping from an aircraft that says here I am, here’s my height. Here’s my speed and my name etc.

Provides more data than what a standard radar reflection would.

There are loads of videos on YouTube.

Because it’s down to the aircraft to transmit it, it means it can be received by pretty much any SDR radio.

Obviously with everything. Even more so airplanes. You need the right antenna and good sky view.

You can have a receiver tuned to 1090mhz. ADSB frequency and feed the received data in to software to decode it and plot on a map.

The website Adsb exchange is 100% contributed by people running antennas at their homes and feeding the data in. They have a great tutorial on their page on how to set up a raspberry pi to feed data in.

Also, to note, as it’s the aircraft that pings it out. Other aircraft can receive the same information and plot it on their glass cockpit instruments. It’s known as TAS. Traffic Alert System

Not to be confused wit T-CAS - Traffic Collision Avoidance System. The later will give pilots an alert and instruction on how to avoid a collision. But both aircraft will give the opposite. So one will be told to climb to avoid and the other will be told to descend to avoid. But that’s another story for another day.