  This paper considers the problem of frequency estimation for a
multi-sinusoidal signal consisting of n sinuses in finite-time. The
parameterization approach based on applying delay operators to a measurable
signal is used. The result is the nth order linear regression model with n
parameters, which depends on the signals frequencies. We propose to use Dynamic
Regressor Extension and Mixing method to replace nth order regression model
with n first-order regression models. Then the standard gradient descent method
is used to estimate separately for each the regression model parameter. On the
next step using algebraic equations finite-time frequency estimate is found.
The described method does not require measuring or calculating derivatives of
the input signal, and uses only the signal measurement. The efficiency of the
proposed approach is demonstrated through the set of numerical simulations.
