Determining coefficients for digital low pass filter given cutoff and boost values for corresponding analog version

摘要

Methods and apparatus are provided for determining coefficients for a digital low pass filter, given cutoff and boost values for a corresponding analog version of the digital low pass filter. Coefficients are determined for a digital low pass filter by obtaining cutoff and boost values for a corresponding analog version of the digital low pass filter; and determining the coefficients for the digital low pass filter based on the obtained cutoff and boost values. The coefficients can be determined, for example, by generating a transfer function, H(s), for the corresponding analog version using the obtained cutoff and boost values: transforming the transfer function, H(s), to a frequency domain characterization, H(z), using one or more bilinear transforms to obtain a plurality of coefficients for an infinite impulse response (IIR) filter; generating the IIR filter using the plurality of coefficients for the IIR filter; and applying an impulse to the IIR filter to obtain the one or more coefficients for the digital low pass filter. In another variation, the coefficients are pre-computed and obtained from a look-up table.

主权项

1. A method for determining one or more coefficients for a digital low pass filter, comprising:
obtaining cutoff and boost values for a corresponding analog version of said digital low pass filter; and determining said one or more coefficients for said digital low pass filter based on said obtained cutoff and boost values for said corresponding analog version of said digital low pass filter.