US 2004/0204880 A1 · Method and system for measuring the energy of a signal

Abstract

A method and a system for measuring the energy of a signal is based on the use of a time-frequency distribution using as kernel a bi-dimensional filter having compact support properties. The two-dimentional filter is applied to the two-dimensional correlation function of the signal to be analyzed. The system includes an acquisition unit for providing samples of the signal, a Hilbert transformer for producing an alytical signals from those samples, and a local correlator for computing the convolutions of a kernel derived from a Gaussian kernel and having compact support properties and instantaneous autocorrelation functions so as to yield generalized instantaneous autocorrelation functions, and a Fourier transformer for determining information related to the energy of the signal from the derived generalized instantaneous autocorrelation functions. The method and system allows a better reduction of false energy observances (interference) while providing good resolution in time and in frequency.

Claims15

Dependent claims

A method for measuring the energy of a signal comprising:

providing a number N of samples n of the signal;
processing each of said N samples of the signal through a Hillbert transform so as to yield N corresponding analytical signals;
for values of n ranging from 1 to N,
providing a window of analysis of length M;
for values of m ranging from 1 to M,
computing an instantaneous autocorrelation function corresponding to each of said values of m;
and
computing the convolution of a CB kernel and said corresponding instantaneous autocorrelation function, yielding a generalized instantaneous autocorrelation function for each combination of said values of m and n;
said CB kernel being defined by
9 K ⁡ ( n , m ) = { exp ( C ⁡ ( 1 ( n 2 + m 2 ) ⁢ ( B M ) 2 - 1 + 1 ) ) if ⁢ ⁢ ( n 2 + m 2 ) ⁢ ( B M ) 2 < 1 0 Otherwise
where B and C are predetermined parameters;
and
applying a Fast Fourier Transform to said generalized instantaneous autocorrelation functions, yielding information about the energy of the signal for each of said N samples.

10 more elements

Dependencies are inferred from the claim text.

Method and system for measuring the energy of a signal

Life of this patent

Method and system for measuring the energy of a signal

Life of this patent

Abstract

Claims15