Patent ID: 6788044
Filing Date: 2004-09-07
Classification: G01R

Abstract:
A frequency change measuring device comprising:at least one frequency divider or frequency dividing a measuring signal having a frequency that is varied by a change in a physical quantity to produce frequency-divided signals; at least one counter for counting the frequency-divided signals to calculate frequency-division numbers; at least one frequency division numbers transmitter for transmitting the frequency division numbers in synchronism with the frequency-divided signals; a frequency division numbers receiver for receiving the frequency division numbers transmitted from the frequency division numbers transmitter to output the frequency division numbers; a reference clock generator for generating reference clocks; and an operations unit for determining a change in the frequency of the measuring signal on the basis of the frequency outputs of the reference clock generator and the frequency division numbers, wherein said operations unit: counts a number of reference clock pulses generated by the reference clock generator during a time period between first and second timings of outputting the frequency division numbers from the frequency division numbers receiver, calculates a difference between the frequency division numbers output at the first and second timings, and determines the change in frequency of the measuring signal based on the number of reference clock pulses generated during the time period and the difference between the frequency division numbers output at the first and second timings.