Enhanced Frequency Resolution in Data Analysis

Luca Perotti, Daniel Vrinceanu, Daniel Bessis

Department of Physics, Texas Southern University, Houston, USA.

DOI: 10.4236/ajcm.2013.33034                

Abstract

We present a numerical study of the resolution power of Padé Approximations to the Z-transform, compared to the Fourier transform. As signals are represented as isolated poles of the Padé Approximant to the Z-transform, resolution depends on the relative position of signal poles in the complex plane i.e. not only the difference in frequency (separation in angular position) but also the difference in the decay constant (separation in radial position) contributes to the resolution. The frequency resolution increase reported by other authors is therefore an upper limit: in the case of signals with different decay rates frequency resolution can be further increased.

Keywords

Frequency Resolution; Z-Transform; Padé Approximations

Conflicts of Interest

The authors declare no conflicts of interest.

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