Communications: electrical – Vehicle detectors – Inductive
Reexamination Certificate
2006-08-28
2008-10-07
Nguyen, Hung T. (Department: 2612)
Communications: electrical
Vehicle detectors
Inductive
C340S931000, C340S907000, C340S908000, C340S917000, C340S515000, C340S551000, C340S561000
Reexamination Certificate
active
07432827
ABSTRACT:
A system and method for activating vehicle sensors which are based on inductive loops. A voltage controlled oscillator is scanned throughout the required frequency range while a balanced mixer, low-pass filter, and detector are arranged to show the presence of a signal from an inductive loop by the amplitude of the resultant signal at a difference frequency. The voltage controlled oscillator is then made to dwell at or near the frequency of the sensor loop by adjusting so as to keep the amplitude of that low-frequency difference as high as possible.
REFERENCES:
patent: 3818430 (1974-06-01), Williams
patent: 3943339 (1976-03-01), Koerner et al.
patent: 3984764 (1976-10-01), Koerner
patent: 3989932 (1976-11-01), Koerner
patent: 4276539 (1981-06-01), Eshraghian et al.
patent: 5057831 (1991-10-01), Strang
patent: 5652577 (1997-07-01), Frasier
patent: 6072408 (2000-06-01), Baer
patent: 6999886 (2006-02-01), Hilliard
A. B. Carlson, “Communication Systems”, (1975), pp. 201-202 McGraw-Hill, USA.
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