| 摘要 |
PURPOSE: A one-third octave band pass filtering method is provided to have a one-stage filter of a digital control way which is capable of fixing a center frequency of each band without using a resistor and a capacitor. CONSTITUTION: A one-third octave band pass filtering method comprises the steps of storing different center frequencies(200), sequentially reading the center frequencies stored in the step(200) to calculate a resistance value according to the sequentially read center frequencies(202), sequentially outputting the resistance values calculated in the resistance value calculating step(204), and sequentially varying a center frequency by use of the resistance value outputted from the resistance value outputting step in order to filter an input signal(206). |
