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 inthecomplexplanei.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.
References
[1]
P. Barone and R. March, “On the Super-Resolution Properties of Prony’s Method,” ZAMM: Zeitschrift Fur Angewandte Mathematik Und Mechanik, Vol. 76, Suppl. 2, 1996, pp. 177-180.
[2]
P. Barone and R. March, “Some Properties of the Asymptotic Location of Poles of Pade Approximants to Noisy Rational Functions, Relevant for Modal Analysis,” IEEE Transactions on Signal Processing, Vol. 46, No. 9, 1998, pp. 2448-2457. doi:10.1109/78.709533
[3]
D. Belkic and K. Belkic, “Optimized Molecular Imaging through Magnetic Resonance for Improved Target Definition in Radiation Oncology,” In: G. Garca Gomez-Tejedor and M. C. Fuss, Eds., Radiation Damage in Biomolecular Systems, Springer Netherlands, Dordrecht, 2012, pp. 411-430.
[4]
C. E. Shannon, “Communication in the Presence of Noise,” Proceedings of IEEE, Vol. 86, No. 2, 1998, pp. 447-457.
doi:10.1109/JPROC.1998.659497
[5]
D. Bessis and L. Perotti, “Universal Analytic Properties of Noise: Introducing the J-Matrix Formalism,” Journal of Physics A, Vol. 42, No. 36, 2009, Article ID: 365202.
doi:10.1088/1751-8113/42/36/365202
[6]
J. Gilewicz and B. Truong-Van, “Froissart Doublets in Padé Approximants and Noise,” Constructive Theory of Functions 1987, Bulgarian Academy of Sciences, Sofia, 1988, pp. 145-151.
[7]
J.-D. Fournier, G. Mantica, A. Mezincescu and D. Bessis, “Universal Statistical Behavior of the Complex Zeros of Wiener Transfer Functions,” Europhysics Letters, Vol. 22, No. 5, 1993, pp. 325-331.
doi:10.1209/0295-5075/22/5/002
[8]
J.-D. Fournier, G. Mantica, A. Mezincescu and D. Bessis, “Statistical Properties of the Zeros of the Transfer Functions in Signal Processing,” In: D. Benest and C. Froeschle, Eds., Chaos and Diffusion in Hamiltonian Systems, Editions Frontières, Paris, 1995.
[9]
D. Bessis, “Padé Approximations in Noise Filtering,” Journal of Computational and Applied Mathematics, Vol. 66, No. 1-2, 1996, pp. 85-88.
doi:10.1016/0377-0427(95)00177-8
[10]
L. Perotti, D. Vrinceanu and D. Bessis, “Beyond the Fourier Transform: Signal Symmetry Breaking in the Complex Plane,” IEEE Signal Processing Letters, Vol. 19, No. 12, 2012, pp. 865-867. doi:10.1109/LSP.2012.2224864
[11]
V. F. Pisarenko, “The Retrieval of Harmonics from a Covariance Function,” Geophysical Journal of the Royal Astronomical Society, Vol. 33, No. 3, 1973, pp. 347-366.