A method includes computing a cross-spectral surface of a signal. The method further includes determining initial frequency estimates to be points on the cross-spectral surface. The method further includes performing a polynomial interpolation to generate an initial frequency polynomial. The method further includes integrating the initial frequency polynomial to generate an initial phase polynomial. The method further includes processing the signal to generate a basebanded signal. The method further includes determining unwrapped phase values of the basebanded signal. The method further includes performing a second polynomial interpolation to generate a residual phase polynomial. The method further includes generating an updated phase polynomial based on the initial phase polynomial and the residual phase polynomial. The method further includes differentiating the updated phase polynomial to generate a polynomial approximation of the time-varying carrier frequency of the received signal.