Doppler compensation in forward-looking STAP radar

For air- and spaceborne MTI radar the clutter Doppler frequency depends on range for all array geometries other than linear sidelooking. This applies particularly to forward-looking arrays. The range dependence of the clutter Doppler causes specific problems in clutter rejection through STAP (space-time adaptive processing) techniques. One aspect is the lack of training data required for adapting the STAP filter. Another aspect is that the STAP filter becomes range dependent. A technique for compensating for the range dependence is proposed. The efficiency of the method is verified by use of clutter data measured with the multichannel radar AER II (airborne experimental radar)