Invention Grant
- Patent Title: Fractional N frequency synthesizer and setting method thereof
- Patent Title (中): 分数N频率合成器及其设置方法
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Application No.: US14596525Application Date: 2015-01-14
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Publication No.: US09584142B2Publication Date: 2017-02-28
- Inventor: Yasuo Ueno , Hiroji Akahori
- Applicant: Icom Incorporated , LAPIS Semiconductor Co., Ltd.
- Applicant Address: JP Osaka
- Assignee: Icom Incorporated
- Current Assignee: Icom Incorporated
- Current Assignee Address: JP Osaka
- Agency: Warner Norcross & Judd LLP
- Priority: JP2014-010920 20140124
- Main IPC: H03B21/00
- IPC: H03B21/00 ; H03L7/197

Abstract:
The calculator calculates the remainder of the division of which the dividend is the minimum accumulated value at which a carryover occurs in the ΔΣ modulator and the devisor is a fractional set value, and calculates the quotient and remainder of the division of which the dividend is the devisor of the previous division and the devisor is the remainder of the previous division until the remainder becomes zero. The abnormal noise determiner determines that the fractional set value causes periodic abnormal noise based on the quotients calculated by the calculator using the fractional set value. The fractional setter sets in the ΔΣ modulator the fractional set value changed to the extent that the output frequency of the VCO does not exceed a given value when the abnormal noise determiner determines that the changed fractional set value does not cause periodic abnormal noise.
Public/Granted literature
- US20150214968A1 FRACTIONAL N FREQUENCY SYNTHESIZER AND SETTING METHOD THEREOF Public/Granted day:2015-07-30
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