The measurement of a patient analyte using wavelet transform analysis is disclosed. Embodiments of the present invention can provide precise identification of erroneous analyte sensor signals and validate good signals. A wavelet transform is applied to a sensor signal to produce a time-scale representation of the sensor signal. In some embodiments a Haar wavelet is used for the transform and energy measurements are derived from the time-scale representation. The time-scale representation of the sensor signal can then be compared to a known sensor signal representation. Embodiments like those disclosed herein are useful in blood glucose monitoring systems in which an analyte sensor signal comprises a blood draw portion and a blood clear portion.
