Logarithmic filter banks

A technique for designing and approximating digital filter banks whose center frequencies are spaced logarithmically is provided. The resonator with the purely imaginary transfer function on the unit circle is treated as the basic element of the bank, and the frequency interpolating filter bank structure is applied. Different pole-zero structures are studied, and an infinite filter bank is explored from the theoretical point of view. The connection to a variant of least-mean-square adaptive filters is described. The results show that these filter banks have good frequency response and allow control of crossover gain, and they are useful for voice and music analysis and tone receivers.<<ETX>>