AEW Radar Space-time Two-dimentional Signal Processing

At the modern war, more and more people have been attention to the problem which is the affect of airborne early warning radar. Compared with the traditional ground-based radar, the airborne early warning radar can better detect in low flying target. When airborne early warning radar at work, the echo from the ground clutter will effect radar system. It is easy covered by main clutter, especially when the target move slowly. space-time two-dimensional adaptive processing is a key technology for airborne early warning radar. The system can not only adapt to the external changing environment, but also can adaptively compensate for the platform motion. Therefore it can suppress ground clutter effectively and can improve the target detection ability of the system. The complete space-time two-dimensional adaptive processing can suppress ground clutter effectively, but the amount of calculation will be very large. In fact it is very difficult to build a system can get the requirements. Therefore it must be to reduce the dimension of STAP so that we can reduce the amount of calculation.This paper introduces the clutter characteristics of the airborne early warning radar. Then it discusses how to suppress the clutter. The problem includes the antenna model, the two-dimensional clutter characteristics and the clutter distribution in different situations on a two-dimensional plane. These problems are the important basis of space-time adaptive processing. Then introduced the structure of two-dimensional adaptive processor which invented by professor and other scholars, namely optimal processor. We build a mathematical modeling for the processor to understand the basic principles of space-time adaptive processing and simulate the optimal processor how to suppress the clutter.At last, the paper mentioned the unified model that space-time adaptive processing to reduce dimensionality. It lists several ways of space-time adaptive processing and introduces the structure、the methods and mathematics conversion of these ways. It simulates some ways in different conditions to analysis the clutter suppression performance. The methods about dimension reduction in this paper, we simulated and verify these methods when the phased array radar that is mounted on aircraft by side. The paper finally prospects and summarizes the space-time adaptive processing, then put forward some opinions of myself.