Phase only matched filter

Great improvements can be made to the usefulness of the correlation peak by using a phase only matched filter (POMF). The matched filter R(m, v) is stripped of its phase information (i.e., the phase angle of the complex data at each pixel) and this is used as the filter in the correlator... 

The FT of the reference is done off line on a computer and is defined as the matched filter R(u,v) for that particular reference r(x,y). In fact, the generation of the filter may be more complicated (to include invariances), and it is advantageous to use only the phase information of the reference FT rather than the full complex amplitude and phase as it gives a more detectable narrow peak [21]. The product of the input FT and the filter then undergoes a further FT to give the correlation in plane 4. The object in the reference r x,y) is centered in the process of generating the filter R(u,v), so that if a correlation peak occurs, its position is directly proportional to the object in the input... 

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