Emergency signal warning system

Electrical audio signal processing systems and devices – Monitoring of sound

Patent

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Details

340902, 324 77E, 324 78D, 324 78F, H04R 2900

Patent

active

047590696

ABSTRACT:
A siren detection system is particularly suited for installation in an automobile for providing a warning to the driver when an emergency vehicle is in the vicinity of the automobile. The system includes a microphone mounted on the automobile. The output of the microphone is supplied to a bank of band-pass filters, each tuned to a different adjacent portion of the frequency range through which the frequency of a siren varies. The outputs of the filters are sampled by an averaging and selection circuit which produces a single output corresponding to the central one of any of the filters producing an output during a preestablished time interval. This output then is compared with the previous output (which indicates the previously selected band-pass frequency) to operate an up/down counter. Whenever successive counts of a preestablished number in the same direction occur, the output of the counter enables an alarm to indicate the presence of a siren operated by an emergency vehicle in the vicinity of the automobile. This system inherently rejects noise in the same frequency range, since random noise signals do not produce the necessary successive output counts from the counter to activate the alarm.

REFERENCES:
patent: 2545218 (1951-03-01), Weber
patent: 3014199 (1961-12-01), Dill
patent: 3158835 (1964-11-01), Hipkins
patent: 3233217 (1966-02-01), Bost
patent: 3293600 (1966-12-01), Gifft
patent: 3371278 (1968-02-01), Gelushia
patent: 3412378 (1968-11-01), Thomas
patent: 3453540 (1969-07-01), Dusheck, Jr.
patent: 3532986 (1970-10-01), Gelushia
patent: 3735342 (1973-05-01), Helliker
patent: 3859623 (1975-01-01), Koehler
patent: 3873963 (1975-03-01), Neal
patent: 4158190 (1979-06-01), Stefanov
patent: 4209769 (1980-06-01), Chronerberry
patent: 4303979 (1981-12-01), Kato et al.
patent: 4380004 (1983-04-01), Coats
patent: 4542525 (1985-09-01), Hopf
patent: 4625206 (1986-11-01), Jensen
patent: 4640134 (1987-02-01), Simmons

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