Title: The double spot modulating type frequency modulation device, wireless transmit device and wireless communication device
Application Number: 200510052956 Application Date: 2005.03.02
Publication Number: 1665140 Publication Date: 2005.09.07
Approval Pub. Date: Granted Pub. Date:
International Classifi-cation: H03L7/197,H03L7/18,H03C3/09
Applicant(s) Name: Matsushita Electric Ind Co., Ltd. Address:
Inventor(s) Name: Kichikawa Hiroyuki, Hirano Shunsuke
Attorney & Agent: ma ying shao yali
Abstract:
     A two-point frequency modulation apparatus is provided that reduces input timing difference and improves modulation accuracy. Two-point frequency modulation apparatus 10 has: PLL circuit 11 ; frequency division ratio generator 13 that generates the frequency division ratio in frequency divider 111 based on first digital baseband signal S 1 and carrier signal; adder 114 that adds second digital baseband signal S 2 to the output signal of loop filter 113 ; a delay index calculator (filter coefficient calculator 17 ) that calculates the delay index based on the magnitude of change in the amplitude of the output signal of adder 114 ; and a delay adjuster (digital filter 18 ) that shifts the phase of one of first digital baseband signal S 1 and second digital baseband signal S 2 according to the delay index so as to reduce the phase difference.
Time: 13
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