Algorithm for generalized harmonic analysis (GHA)

Generalized harmonic analysis (GHA) proposed by Wiener (1958) is a fine tool in time-frequency resolution because it expresses signal using almost-periodic function. However, the method is rarely utilized because it involves a large amount of calculation. High efficiency algorithm for GHA was developed first by Hirata, and was further improved recently in a reduction of calculation amount. However, they were not enough in accuracy. Starting from the Hirata's algorithm, the authors have achieved a high-speed, highly accurate GHA algorithm by improvement in the calculation method of sine and cosine coefficients and subdivision of a frequency scale.