> Radar is a system that uses radio waves to determine the distance (ranging), direction (azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track aircraft [...]
> A radar system consists of a transmitter producing electromagnetic waves in the radio or microwave domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving information about the objects' locations and speeds.
The OP's project only passively receives the digital location information of each airplane transmitted by the airplane itself. The project does not transmit radio waves nor do any physical determination of the plane's location.
See also: https://en.wikipedia.org/wiki/Primary_radar (true radar), https://en.wikipedia.org/wiki/Primary_radar (ADS-B, which is what the OP receives)