A solution to the adaptive nulling problem with a look-direction constraint in the presence of coherent jammers

A new adaptive technique is presented that is capable of nulling coherent, as well as incoherent, jammers while maintaining a fixed gain in the look direction. The technique depends on the use of new kind of correlation matrix and a subtractive preprocessor. It does not require any spatial smoothing. It requires elements to null coherent jammers in the presence of noise. The matrix used in the technique is such that its unbiased estimate in the presence of noise can be obtained. This helps making the algorithm robust to noise in finding the desired weight vector to be used by the array.