An Accurate and Efficient Two-step Velocity Estimation Method for Moving Targets for Airborne Forward-Looking Scanning Radar

Relative velocity estimation is a key challenge for moving target detection in current forward-looking scanning radar-aerial collision avoidance systems. Since the conventional methods suffer from low precision or heavy computation load for fast-moving target motion estimation, this paper proposes an accurate and efficient two-step estimation method that improves the efficiency and accuracy. To improve the estimation efficiency, the first step utilizes Radon transform to narrow the velocity interval which reduces the number of searches. The second step is devoted to fine searching the velocity interval by the minimum entropy criterion, which ensures high estimation accuracy. In the search process, a two-point interpolation method is proposed to reduce the search time and further improve the estimation efficiency. Theoretical and simulation experimental analyses provide qualitative and quantitative evaluations of the efficiency and accuracy of the proposed method.