Title:
DEVICE FOR DETECTING TONE SIGNAL
Document Type and Number:
Japanese Patent JP3909183
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a system capable of detecting and demodulating a tone signal by using a CPU shared by other control.
SOLUTION: This device is provided with a 1st sampling means 3 sampling an input signal with a 1st sampling frequency, a 1st offset eliminating means 5 eliminating an offset component, a binarizing means 6 binarizing the signal, a spectrum measuring means 7 measuring a frequency spectrum, a 2nd sampling means 4 sampling the input signal with a fixed sampling frequency, a lowpass selecting means 9 selecting a lowpass component, a 2nd offset eliminating means 10 eliminating an offset component, a period measuring means 11 measuring a signal period and designating the 1st sampling frequency, and a deciding means 12 performing cross-correlation processing of the spectrum measured by the spectrum measuring means on the basis of the measured period and deciding a tone signal.
Inventors:
Hiroshi Maekoku
Application Number:
JP2000054499A
Publication Date:
April 25, 2007
Filing Date:
February 29, 2000
Export Citation:
Assignee:
Icom Co., Ltd.
International Classes:
G01R23/16; H04M1/00; H04L27/00; H04L27/144; (IPC1-7): H04M1/00; G01R23/16; H04L27/00; H04L27/144
Domestic Patent References:
| JP9083386A | ||||
| JP10126454A | ||||
| JP5211528A | ||||
| JP56110373A | ||||
| JP8289037A |
Attorney, Agent or Firm:
Katsunori Sugimoto