A Novel Window For High-Resolution Fourier Transforms
L.J. Griffiths · 2005
This paper suggests a new data multiplication window for use with the Fourier Transform. The window is complex and consists of a linear FM chirp which spans the range 0 to 21r. Windowing in this manner is shown to be particularly useful for complex data signals such as those observed at the outputs of in-phase and quadrature component receivers. As such, it has application to both communications and radar problems. For the case of an input consisting of a single complex sinusoid, the new window produces an extremely sharp null located exactly at the frequency of the input sinusoid. As such, it has resolution properties far superior to those available via more conventional windowing techniques such as the raised cosine. Examples are presented showing clear indications of frequency shifts as small as 1/8 bin. Applications to real data environments are discussed.