Airborne Radar Clutter Suppression Technology

Radar equipped in an airplane has many merits such as seeing things beyond the visibility of Ground-based radar, flexibility in application. It plays an important part and is widely used in national defence. Its value of application has been testified in the war of Gulf and Iraq. So it attracts great attention of many nations in the world. But airborne Radar will face highly complicatied clutter environment. The complexities of clutter back ground mainly embody in large amplitude interference of ground clutter, clutter spectrum spread caused by platform movement effect. And the characteristics of the ground clutter change as well as time change. The key to the settlement of the question of effective detection of ground and low air targets lies in adaptive of effective clutter suppression in airborne Radar. Conventional airborne radar clutter suppression techniques utilize the diffrernce in Doppler frequency domain between clutter and target returns to suppress clutter. Doppler frequency domain one-dimension adaptive filtering, which usually used in main lobe clutter suppression. For slow targets whose Doppler frequencies fall into clutter Doppler band, the performance of frequency domain one-dimension filtering is seriously degraded. In an airborne radar, there is interdependence between the clutter Doppler frequency and spatial position. Space-time adaptive processing(STAP) utilizes this interdependence to suppress clutter and get perfect main-lobe and side-lobe clutter suppression. But STAP is too complex to be realized.This dissertation focuses on studying adaptive clutter suppression of airborne Radar. It not only gives impetus to the application of adaptive filtering and spectral estimation but also have important significance to project development. Main content can be concluded as following.The characteristics of the ground clutter are analyzed and presented. The development and the theories of clutter suppression of airborne Radar are desicribed systematically.The performance of adaptive spectral estimation is analyzed. The AMTI algorithm and adaptive spectral estimation algorithm are compared through the results of computer simulations and a pragmatic radar data.