LAUSR

The dynamically changing ionospheric conditions are the biggest impediment to realizing the ideal performance in long range for over-the-horizon radar (OTHR). Most related studies focus on developing the signal processing techniques and antenna arrays design. However, ionosphere clutter derives from the interaction between radar signal and the ionosphere, and it exhibits different behaviors in 3-D. OTHR should have the ability to sense when and where (in range) a certain type of ionosphere clutter appears before proposing the appropriate suppression scheme. Therefore, this article aims at identifying the various types of ionosphere clutter in Earth’s middle-latitude regions and characterizing them in terms of temporal, Doppler, azimuth, range, and overall amplitude distribution domain, thus establishing a multidimensional information profile. An experimental OTHR has been developed to monitor the surrounding oceans in middle-latitude area; we collected a sufficient real radar return data for two years running and then selected data specifically designed to observe the ionosphere clutter. Then, we identify the various types of ionosphere clutter and catalog their multidimensional characteristics. A knowledge of where a certain type of ionosphere clutter appears and pertinent information are essential for developing the appropriate clutter mitigation scheme in real time.