Portable anti-theft device
US5223815A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 1993 |
| Grant date | Jun 29, 1993 |
| Priority date | — |
| Expiry date | Jan 5, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B21/0247
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A portable anti-theft system and method for sounding an alarm which is a speech synthesizer when a first portable unit and a second portable unit become separated by a predetermined distance is disclosed herein. The system comprises transmitter means in the first portable unit for transmitting a signal, receiver means in said second portable unit for receiving the signal transmitted by the transmitter means, signal strength determination means in communication with the receiver means for comparing the strength of the received signal with a predetermined signal comprising speech synthesizing means for making an announcement when the signal strength determination means has determined that the strength of the received signal is less that the predetermined signal strength value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.