US5021794A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Personal emergency locator system
Assignee: Individual
•
Filing: 1989-08-15
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Granted: 1991-06-04
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Expires: 2009-08-15
Abstract
Abstract The radio transmitter in a miniaturized transceiver concealed on a person to be located, such as a lost child, is activated and transmits a coded UHF radio homing signal upon receipt of an initiating signal containing the child's address code. The initiating signal is automatically transmitted by a repeater station in response to an audible "panic signal" containing the address code and contains the identical address code. The panic signal is a pulse tone produced by a hand held tone generator activated by the child's parent and is transmitted to the repeater station by telephone. Tracking vehicles are provided with automatic UHF radio direction finding and distance measuring equipment for locating the source of the homing signal. Stored information concerning the child can be transmitted to the tracking vehicles.
Inventors
- 👤 Robert A. Lawrence
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:51
CPC Classifications
G; G08; G08B; G08B21/00; G08B21/02; G08B21/0202; G08B21/0222; G01; G01S; G01S13/00; G01S13/74; G01S5/00; G01S5/02; G01S5/04; G08B21/0241; G08B21/0247; G08B21/0263; G08B21/028; G08B3/00; G08B3/10; G08B3/1008; G08B3/1016; G08B3/1083
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
159 words
A telephone-activated personal emergency locator system, comprising: portable signal generating means adapted to be actuated by an individual interested in locating a lost or abducted person, said signal generating means generating an audible digital pulse-tone signal containing a discrete encoded address for transmission by means of a telephone system; repeated means effectively connected to said telephone system for receiving audible digital pulus-tone signals transmitted by said telephone system, said repeater means including radio transmitter means for generating and transmitting a radio-frequency initiating signal containing said encoded address upon receipt of a digital pulsetone signal from said signal generating means. radio transceiver means carried by a person to be located for receiving an initiating signal transmitted by said repeater and transmitting a radio homing signal containing said encoded address in response to said initiating signal; and radio receiver means for receiving and identifying said homing signal and determining there from the bearing and distance from said receiver to said transceiver.
Claim 2
Dependent Claim
159 words
A telephone-activated personal emergency locator system, comprising: portable signal generating means adapted to be actuated by an individual interested in locating a lost or abducted person, said signal generating means generating an audible digital pulse-tone signal containing a discrete encoded address for transmission by means of a telephone system; repeated means effectively connected to said telephone system for receiving audible digital pulus-tone signals transmitted by said telephone system, said repeater means including radio transmitter means for generating and transmitting a radio-frequency initiating signal containing said encoded address upon receipt of a digital pulsetone signal from said signal generating means. radio transceiver means carried by a person to be located for receiving an initiating signal transmitted by said repeater and transmitting a radio homing signal containing said encoded address in response to said initiating signal; and radio receiver means for receiving and identifying said homing signal and determining there from the bearing and distance from said receiver to said transceiver.
Claim 3
Dependent Claim
19 words
The personal emergency locator system of claim 1, wherein said homing signal is in the radio ultrahigh frequency range.
Claim 4
Dependent Claim
21 words
The personal emergency locator system of claim 2, wherein said radio receiver includes an automatic direction finder and distance measuring equipment.
Claim 5
Dependent Claim
14 words
The personal emergency locator system of claim 3, wherein said radio receiver is mobile.
Claim 6
Dependent Claim
15 words
The personal emergency locator system of claim 4, comprising a plurality of such radio receivers.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-06-03 | 1994-12-03 | 1995-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-03 | 1998-12-03 | 1999-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-03 | 2002-12-03 | 2003-06-04 | $7700.00 | Window Closed / Lapsed |