Apparatus and method for detecting the onset of a frequency shif

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324 78F, 324 78Q, 328138, 329145, 375 80, H03D 306

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active

044854480

ABSTRACT:
An incoming signal is tested for the presence or onset of a frequency shift keyed (FSK) signal which alternates at a known rate between two unknown frequencies separated by a known frequency shift. The incoming signal is time delayed an odd multiple of the keying period and the delayed signal is multiplied by the incoming signal to produce sum and difference frequencies when the FSK signal is present. The difference frequency is selected by filtration and multiplied by a time delayed version of itself to produce a steady phase signal. The steady phase signal is extracted by filtration, demodulated and integrated to produce a useable detector signal for comparison with a threshold level.

REFERENCES:
patent: 3372335 (1968-03-01), Takada
patent: 3758852 (1973-09-01), Nowell et al.
patent: 3866124 (1975-02-01), Wycoff
patent: 3984770 (1976-10-01), Chu
patent: 4024414 (1977-05-01), Gurry
patent: 4203113 (1980-05-01), Baghdady
patent: 4344328 (1982-08-01), Hawkins
patent: 4349878 (1982-09-01), Grimm
patent: 4363138 (1982-12-01), Franklin et al.
patent: 4419758 (1983-12-01), Dorey
patent: 4423519 (1983-12-01), Bennett, Jr. et al.

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