POWER TRANSMISSION DEVICE, SPROCKET USED FOR THE DEVICE, AND PASSENGER CONVEYOR

摘要

PURPOSE: To extend word length without attenuating the level of a high frequency component even in the case of using Lagrange's interpolation by interpolating over-sampled input data by the number of bits longer than the input data based upon the sampling point of the input data and interpolating the interpolated input data again by the data of an intermediate bit based upon the sampling point of the interpolated input data. CONSTITUTION: The sampling frequency(SF) of inputted data X (n) is increased N times through an over-sampling filter 1. A DSP 2 samples the data X (n) at SF=1/(N.SF) and generates data Y (n) on the intermediate of the sampling point of the data X (n). Then the data Y (n) are sampled at SF=1/(N.SF) and data Z (n) are generated on an intermediate sampling point (N (n)). The data Z (n) are supplied to a decimation filter 3 and N-times SF is down-sampled to 1/N times.