| 摘要 |
PROBLEM TO BE SOLVED: To provide a frequency measuring device of a short-gate count system capable of achieving a high-speed circuit operation and reduction in electric power by simplifying a circuit such as a filter as much as possible in the frequency measuring device.SOLUTION: The frequency measuring device includes: a short-gate time counter (10) for counting the frequency of a signal to be measured and generating a continuous binary count output; and a low-pass filter (20) for removing high frequency components from the continuous binary count output and formed of filters of a plurality of stages. At least a part (12) of the short-gate time counter and a filter (21) of the first stage of the low pass filter are integrally formed as a circuit (13). The filter of the first stage is a moving average filter to which the continuous binary count output is input and which provides a continuous binary output having reduced high-frequency components. A filter (22) of the second stage applies intermittent average value calculation to a continuous binary output string of the moving average filter and provides an output having reduced high-frequency components. |
