发明名称 |
Frequency tracking method and apparatus, and Doppler velocity meter using the same |
摘要 |
This invention has as its object to provide a frequency tracking method, a frequency control apparatus (tracking apparatus) using this method, and a Doppler velocity meter using the same, which easily and quickly allow the center frequency of a band pass filter to coincide with the frequency of an input signal even when an input signal suffers from a large level drift. A tracking method for a center frequency of a band-pass filter relates to a method including the deviation information detection step of detecting deviation information of the frequency of a signal to be input to the band-pass filter or a signal output from the band-pass filter with respect to the center frequency of the band-pass filter, the deviation information detection step including at least the step of detecting the deviation direction, and the changing step of changing the center frequency of the band-pass filter on the basis of a detection result in the detection step of detecting the deviation information including the deviation direction, thereby adjusting the center frequency of the band-pass filter to coincide with the frequency of a signal to be filtered through the band-pass filter.
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申请公布号 |
US5696578(A) |
申请公布日期 |
1997.12.09 |
申请号 |
US19930060533 |
申请日期 |
1993.05.13 |
申请人 |
CANON KABUSHIKI KAISHA |
发明人 |
ISHIDA, YASUHIKO;KADOWAKI, HIDEJIRO;TAKAMIYA, MAKOTO;ASHIWA, JUN;KATO, SHIGEKI;UEDA, SHINJI |
分类号 |
G01P3/36;G01S7/491;G01S17/58;(IPC1-7):G01P3/36;H03B1/00 |
主分类号 |
G01P3/36 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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