Infinite impulse response filter and digital input signal filtering method with low quantization effect

摘要

The parallel IIR filter 100 has a low quantization effect and includes a multiplier 103 for multiplying a digital input signal by a constant and an arbitrary number of biphasic filters 104 and 105. The multiplier 103 output and each biquad filter 104,105 are summed together in a summation device 106 to provide an output signal of the IIR filter 100. The IIR filter 100 converts its transfer function into a serial form transfer function , And then the constant is calculated as the product of the respective serial form of the biphasic constant of the bids. The IIR filter 100 partially decomposes the series transfer function to provide a first order term and calculates the first order term molecular coefficient. The disjointed pair of terms is recombined to provide a parallel form transfer function from which the parallel form factor is taken and applied to the biquad filter 104,105.