Title:
信号検出装置
Document Type and Number:
Japanese Patent JP5779022
Kind Code:
B2
Abstract:
A signal detection apparatus detects the frequency of an input signal without using a PLL. The detection apparatus includes a first and a second orthogonalizer, a phase difference calculator and an integrator, to control the variable coefficient a1 of a band-pass filter. Information e[k]=M·sin(phi) representing the phase difference phi between the input data x[k] and the output data y[k] is calculated with the first and second orthogonalizers and the phase difference calculator. The sign of e[k] is inverted and a predetermined integral calculation is performed with the integrator, and the calculated integral value is set as the coefficient a1 of the band-pass filter. Every time input data x[k] is input, the coefficient a1 is changed by reducing it when e[k]>0 and increasing it when e[k]<0. Thus, the frequency of the output signal of the band-pass filter is matched to the input signal.
Inventors:
Kitano Toyokazu
Application Number:
JP2011157657A
Publication Date:
September 16, 2015
Filing Date:
July 19, 2011
Export Citation:
Assignee:
Daihen Co., Ltd.
International Classes:
G01R23/12; G01R23/10; G01R25/04
Domestic Patent References:
| JP2008165125A | ||||
| JP2005229312A | ||||
| JP2005003530A | ||||
| JP2004336152A | ||||
| JP57181712A |
Attorney, Agent or Firm:
Minoru Yoshida
Tatsuya Tanaka
Tsukasa Senba
Yasumitsu Suzuki
Nao Usui
Tatsuya Tanaka
Tsukasa Senba
Yasumitsu Suzuki
Nao Usui
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