A novel simple adaptive spectral analysis zoom for narrow-band signals

In [1] a new spectral analysis zoom technique for narrow-band signal applications was presented. This zoom-technique is based on subband decomposition and linear prediction. The subband-decomposition idea applied to both FFT [2], [3] and DCT [4], [5] to find these transforms with less computations, is used in [1] in combination with the linear prediction algorithm to implement a new zoom technique with higher spectral resolution efficiency than other techniques. In this work the new algorithm computational complexity is studied. The zoom capability of this subband decomposition zoom technique is also explained by considering many factors such as the gain of the linear prediction modelling and the power spectral density and autocorrelation between the linear prediction coefficients [6]. The accuracy of the technique in terms of the prediction error and minimum allowable signal to noise ratio is also included in this paper. Finally, the adaptive capability of the subband-FFT is included in the zoom algorithm to select the band of most energy (the band to be zoomed).