Apparatus and method for position reporting

• US 5,027,314 A
• Filed: 03/07/1990
• Issued: 06/25/1991
• Est. Priority Date: 03/17/1988
• Status: Expired due to Term

• Current Assignee: Versus Technology, Inc. (Midmark Corporation)
• Original Assignee: United Manufacturing Industries Incorporated
• Inventors: Duncan, Wayne, Linwood, Gary
• Primary Examiner(s): Harkcom, Gary V.
• Assistant Examiner(s): Merecki, John A.
• Application Number:
  US07/490,144
• Time in Patent Office: 475 Days
• Field of Search: 340/573, 340/825.36, 340/825.44, 340/825.49, 340/825.52, 340/825.54, 379/38, 364/200 MS File, 364/900 MS File, 364/403, 235/375, 235/385
• US Class Current: 701/300
• CPC Class Codes: G06K 17/0022 arrangements or provisious for transferring data to distant stations, e.g. from a sensing device "transfer between computer elements G06F13/00 "; data-transmission H04L
• CPC Class Codes: G06K 7/1097 Optical sensing of electronic memory record carriers, such as interrogation of RFIDs with an additional optical interface
• CPC Class Codes: G07C 9/28 the pass enabling tracking or indicating presence
• CPC Class Codes: G08B 1/08 using electric transmission ; transformation of alarm signals to electrical signals from a different medium, e.g. transmission of an electric alarm signal upon detection of an audible alarm signal
• CPC Class Codes: G08B 25/10 using wireless transmission systems G08B25/009 takes precedence

Abstract

A system and method for tracking a number of subjects in a plurality of areas is shown to include a plurality of transmitters, wherein at least one transmitter is associated with each subject, each transmitter transmits a light based signal representative of an identifying code unique to that transmitter, a plurality of receivers, wherein at least one receiver is associated with each area, each receiver converts transmitted light based signals to electrical signals and validates the electrical signal to determine whether such electrical signals are representative of the unique identifying codes associated with the transmitters, and a central processing member, connected to each of the receivers, for recording those electrical signals which are representative of the unique identifying codes for recording the receiver which determined that such electrical signals are representative of the unique identifying codes associated with the transmitters and for determining in which area the transmitter is actually located.

Claims

1. A system for tracking a number of subjects in a plurality of areas comprising:

a plurality of transmitters, wherein at least one transmitter is associated with each of said subjects, each of said transmitters comprising transmission means for transmitting a light based signal representative of an identifying code unique to that transmitter;

a plurality of receivers, wherein at least one of said receivers is associated with each of said areas, each of said receivers comprising a converter for converting a transmitted light based signal to an electrical signal and a validation circuit for processing said electrical signal to determine whether said electrical signals are representative of the unique identifying codes associated with said transmitters; and

processor means, connected to each of said receivers, for recording those electrical signals which are representative of said unique identifying codes, for recording the receiver which determined that such electrical signals are representative of the unique identifying codes associated with said transmitters and for determining in which of said areas said transmitters are located, wherein said processor means comprises scanning means for scanning said receivers and accumulating means for accumulating with respect to each transmitter those areas in which receivers have determined that an electrical signal is representative of the unique identifying code associated with that particular transmitter and for accumulating a badge count for each accumulated area, said badge count being representative of the number of times a receiver has determined that an electrical signal is representative of the unique identifying code associated with that particular transmitter.

2. The system of claim 1, wherein said light based signals are infra-red radiation based signal.

3. The system of claim 1, wherein each of said receivers includes at least two converting means for converting transmitted light based signals to electrical signal.

4. The system of claim 1, wherein each of said transmitters is a portable device associated with an individual subject.

5. The system of claim 1 wherein said validation circuit comprises a computer for comparing said electrical signal to a second electrical signal representative of said unique identifying codes.

6. The system of claim 1, wherein said validation circuit comprises a memory for storing said unique identifying codes, and wherein the determination of whether an electrical signal is representative of a unique identifying code associated with said transmitters is achieved by comparing said electrical signal to said unique identifying codes stored in said memory.

7. The system of claim 1, wherein said processor means further comprises comparison means for comparing the accumulated number of areas and said bade counts to respective reference numbers and for generating an indication of such comparisons.

8. The system of claim 1, wherein said processor means further comprises location means for determining the location of said transmitters in relation to the indication from said comparison means.

9. A method for tracking a number of subjects in a plurality of areas in a system wherein at least one transmitter is associated with each of said subjects, each transmitter being capable of transmitting a light based signal representative of an identifying code unique to that transmitter, comprising the steps of:

converting, in a receiver, the transmitted light based signal to an electrical signal and validating said electrical signal to determine whether said electrical signal is representative of the unique identifying codes associated with said transmitter;

recording those electrical signals which are representative of said unique identifying codes;

recording the receiver which determined that such electrical signals are representative of the unique identifying codes associated with said transmitters; and

determining in which of said areas said transmitters are located, wherein the recording the receiver and the determining steps comprise the steps of scanning said receivers and accumulating with respect to each transmitter those areas in which receivers have determined that an electrical signal is representative of the unique identifying code associated with a particular transmitter and accumulating a badge count for each accumulated area, said badge count being representative of the number of times a receiver has determined that an electrical signal is representative of the unique identifying code associated with the particular transmitter.

10. The method of claim 9, wherein the step of validating the electrical signal comprises the step of comparing said electrical signal to a second electrical signal representative of said unique identifying codes.

11. The method of claim 9, further comprising the steps of comparing the accumulated number of areas and said badge counts to respective reference numbers and generating an indication of such comparisons.

12. The system of claim 11, further comprising the step of determining the location of said transmitters in response to the indication of comparisons.