Personal security system and apparatus therefor

• US 5,225,809 A
• Filed: 12/24/1990
• Issued: 07/06/1993
• Est. Priority Date: 12/24/1990
• Status: Expired due to Fees

• Current Assignee: Mayday Healthcare
• Original Assignee: Mayday Healthcare
• Inventors: Bunn, Charles G.
• Primary Examiner(s): MULLEN, THOMAS J
• Application Number:
  US07/632,526
• Time in Patent Office: 925 Days
• Field of Search: 340/574, 340/505, 340/825.54, 340/525, 340/825.08, 340/693, 340/636, 340/825.49, 340/311.1, 358/105, 358/108, 455/53, 455/53.1, 455/54.1, 455/54.2, 455/95, 455/128, 364/520, 364/575, 342/44, 342/443-445, 342/451, 343/894, 343/702
• US Class Current: 340/574
• CPC Class Codes: G01S 5/04 Position of source determined by a plurality of spaced direction-finders
• CPC Class Codes: G08B 25/009 Signalling of the alarm condition to a substation whose identity is signalled to a central station, e.g. relaying alarm signals in order to extend communication range
• CPC Class Codes: G08B 25/016 Personal emergency signalling and security systems emergency non-personal manually actuated alarm activators G08B25/12

Abstract

A personal security system and process for use thereof wherein customers of a security service are provided with personal transmitters capable of selectively transmitting one or more radio signals at a desired frequency, the signals representing the particular character of service that is desired. A number of antenna/transmitters are located in evenly spaced relation in the geographical area and correspond to a computer grid work of the geographical area. The antenna/transmitters receive signals having X and Y axes from the personal transmitters, amplify the signals and transmit them to signal processing equipment. The signal processing equipment includes an automatic direction finding circuit capable of receiving the X and Y axes components of the personal transmitter signal and the vertical elevation of the signal in order to yield an ADF signal output reflecting the location of the signal. The ADF output signal is then processed by means of a computer such that the signal is displayed on a cathode ray tube impressed with a map of the geographical area and the antenna grid work to thus display a signal representing the position of the personal transmitter on a grid of the geographical area. This signal can be further processed to locate the personal transmitter on a small portion of the grid work to thus provide service personnel with the capability of efficiently locating and servicing the signal transmitting customer'"'"'s needs.

Claims

1. A method for location of a mobile personal transmitter within a geographical area for the provision of requested services desired by a person selectively transmitting a coded frequency from said mobile personal transmitter, comprising:

(a) transmitting a selected radio frequency signal from said mobile personal transmitter having the capability of transmitting selected ones of a plurality of signals each having X and Y signal axes components, said selected signal designating a desired service;

(b) receiving said selected radio signal by two or more of a plurality of antenna/transmitters strategically positioned in said geographical area and transmitting said received signal to a base station antenna located within said geographical area; and

(c) computer processing and plotting of said X and Y signal axes components of said selected signal by means of a computer having a cathode ray tube and having software presenting on said cathode ray tube a computer grid-work representing said geographical area, thus identifying the location of the radio signal emitted by said mobile personal transmitter relative to said computer grid-work of said geographical area.

2. The method of claim 1, wherein:

said computer processing includes processing said X axis and axis signal components with automatic direction finding circuitry to provide an ADF signal representing the location of said mobile personal transmitter relative to said grid-work representing said geographical area.

3. The method of claim 1, wherein:

(a) said antenna/transmitters are positioned at predetermined locations relative to said grid-work; and

(b) said computer processing includes averaging the X axis and Y axis signal components from each antenna/transmitter to thus provide an averaged signal that is processed and displayed by said cathode ray tube of said computer on a computerized map of said geographical area.

4. The method of claim 1, including:

transmitting from said mobile personal transmitter one of a plurality of radio signals coded to a particular service that is requested at the site of said mobile personal transmitter.

5. The method of claim 1, including:

accomplishing said computer processing by means of said computer software developed to present a map of said geographical area on said cathode ray tube of said computer and by providing said computer with a set of coordinates, causing the computer software to display the particular quadrant within which the radio signal of the mobile personal transmitter emanates to thus provide for location of the source in the geographical area to thus enhance efficient location of the person for provision of the requested assistance.

6. The method of claim 5, including:

amplifying the signal of said mobile personal transmitter by means of said antenna/transmitters being narrowly tuned to the specific frequency of said mobile personal transmitter, said antenna/transmitters amplifying the X axis and Y axis signal components of the mobile personal transmitter signal, and transmitting said amplified signal to said base station antenna which is coupled with an ADF signal processor, thereby insuring that said ADF signal processor will establish an average between only two of said antenna/transmitters.

7. A personal security system for a limited geographical area such as a large city, comprising:

(a) a plurality of mobile personal transmitters each having a plurality of signal transmitting circuits of differing frequency, each of said signal transmitting circuits capable of generating a low VHF band signal having X and Y axes components;

(b) means in each mobile personal transmitter permitting manual selection and activation of one of said plurality of signal transmitting circuits for transmission of a signal of a desired frequency;

(c) a plurality of antenna/transmitters being strategically located within said geographical area, said antenna/transmitters being narrowly tuned to designated receiving frequencies of said mobile personal transmitters and receiving, amplifying and transmitting X axis and Y axis signal components of said mobile personal transmitters;

(d) base antenna means for receiving signals from said antenna/transmitters; and

(e) computer means being interfaced with said base receiving means and being operative to receive said X axis and Y axis signal components of said antenna/transmitters and process said X axis and Y axis signal components of said antenna/transmitters according to software instructions and to plot said X axis and Y axis signal components on a computerized grid-work of said geographical area thus identifying the location of signal transmission from said mobile personal transmitters on said computerized grid-work.

8. The personal security system as recited in claim 7, wherein:

(a) said plurality of said antenna/transmitters are located in substantially evenly spaced relation in said geographical area to thus form an antenna grid-work corresponding to said computerized grid-work of said geographical area; and

(b) said antenna/transmitters each include automatic direction finding circuitry for processing said X axis and Y axis signal components for establishing a bearing from said antenna/transmitters to the location of said mobile personal transmitters relative to said grid-work of said geographical area.

9. The personal security system of claim 8, wherein:

said antenna/transmitters each include three axis signal components for establishing the position of the mobile personal transmitters in terms of X, Y and Z axes signal components on said grid-work and

transmitting signals identifying the position of said mobile personal transmitters to said base antenna means.

10. The personal security system of claim 9, wherein:

said antenna/transmitters transmit signals representing battery voltage and transmission strength, said signals being processed by said computer to provide appropriate indications when service is required.

11. The personal security system of claim 10, wherein:

(a) a base station antenna is provided to receive signals transmitted by said antenna/transmitters;

(b) automatic direction finding circuitry is coupled with said base station antenna and thus receives and averages said X axis and Y axis signal components to provide an ADF output; and

(c) said computer means receives said ADF output and processes it to yield X axis and Y axis position signals for location of said mobile personal transmitters relative to said computerized grid-work of said geographical area.

12. The personal security system of claim 11, wherein:

said computer means includes software programmed to identify specific structures on individual grids of said computer grid-work and capable of displaying a single computer grid section and the position of the signals transmitted by said mobile personal transmitters relative to said computer grid-work to thus enable personnel to efficiently locate a mobile personal transmitter and the person requesting assistance.

13. A transmitter/antenna for a personal security system having the capability of identifying the location of a signal transmission in a specific geographical area, comprising:

(a) an antenna housing having a lower housing section composed of metal and having an upper housing section composed of a polymer;

(b) a battery pack being located in said lower housing section and providing electrical power to said transmitter/antenna;

(c) a plurality of printed circuit boards being supported within said lower housing section and defining a major portion of the electrical circuitry of said transmitter/antenna; and

(d) a plurality of transmit and receive antennas being provided in said upper housing section for radio direction finding and being positioned within said upper housing section for transmitting and receiving radio signals propagated through said polymer material of said upper housing section.

14. The transmitter/antenna of claim 13, wherein:

said upper and lower housing sections are in threaded assembly;

15. The transmitter/antenna of claim 13, including:

(a) a circuit board holder being supported within said lower housing section; and

(b) said printed circuit boards being supported by said circuit board holder.