This article details a fascinating project where a researcher successfully used signals from the NISAR radar-imaging satellite to create a passive radar system. By utilizing the satellite's L-band chirp signal, reflected off the landscape, and comparing it to a direct signal, a topographical image could be generated. The setup involved using GNSS antennas and an SDR (Software Defined Radio) with a Raspberry Pi to record and process the signals. While not producing high-resolution images, the experiment successfully demonstrated the feasibility of using satellite signals for passive radar, even with relatively simple and inexpensive equipment.
This Hackaday article details a DIY passive radar system built to track aircraft by analyzing existing radio wave reflections. Unlike traditional radar, this system doesn't emit its own signal, instead relying on signals already present in the environment, specifically those used for ADS-B transmissions. The system uses a nine-element Yagi antenna to capture these reflections and a computer program to compare the direct and reflected signals, identifying aircraft.
An aircraft monitor based on Charlie Gerard's JavaScript Aircraft Radar System. It requires an RTL-SDR USB dongle and a WebUSB capable browser.
