1. A method for determining signal parameters for one or more tones in an input signal, the method comprising: (a) receiving samples of the input signal, wherein the input signal includes the one or more tones; (b) operating on the samples to generate a transform array, wherein the transform array includes a positive frequency image and a negative frequency image for each of the one or more tones; (c) identifying frequency locations of one or more first magnitude peaks in the transform array; (d) computing a frequency estimate, amplitude estimate and phase estimate for each of the one or more tones based on complex values of the transform array in a neighborhood of a corresponding one of the frequency locations; (e) correcting the complex values of the transform array in the frequency neighborhood of each frequency location based on the frequency estimates, amplitude estimates and phase estimates for the one or more tones; (f) computing an improved frequency estimate, improved amplitude estimate and improved phase estimate for each of the one or more tones based on the corrected complex values in the neighborhood of the corresponding frequency location; (g) storing the improved frequency estimates, improved amplitude estimates and improved phase estimates for the one or more tones.