US 5,995,046 AGranted

Radio geo-location system with advanced first received wavefront arrival determination

AssigneeWidata Corporation

InventorsDonald K. Belcher, Robert W. Boyd, Michael A. Wohl

Life of this patent

Estimating the term…

Loading patent…

Abstract

An asset management radio location system uses time-of-arrival differentiation for random and repetitive spread spectrum, short duration pulse `blinks` from object-attached tags, to provide a practical, continuous identification of the location of each and every object within an environment of interest, irrespective whether the object is stationary or moving. Correlation-based RF processors determine which signals received spatially diverse antennas coupled to tag transmission readers are first-to-arrive signals as transmitted from any blinking tag. An object location processor carries out time-of-arrival differentiation of first-to-arrive transmissions from any blinking tag to determine where the respective object is located within the environment.

Claims12

Dependent claims

A system for identifying the locations of objects within a monitored environment, using time-of-arrival differentiation for transmissions from tags disposed with said objects, as detected at a plurality of spaced apart tag transmission monitoring locations for said monitored environment comprising:

for each of said objects, a respective tag disposed therewith containing a tag transmitter which is operative to transmit a signal encoded with information representative of the identification of said each object;
each of said plurality of spaced apart tag transmission monitoring locations having a plurality of mutually diverse antennas coupled to associated tag transmission readers which are operative to detect said signals transmitted by said tag transmitter;
reader output processors operative to process signals detected by associated tag transmission readers and to determine which signals received by said tag transmission readers are first-to-arrive signals as transmitted from said tag transmitter;
and
an object location processor coupled to said reader output processors, and being operative to carry out time-of-arrival differentiation of said first-to-arrive signals transmitted from said tag transmitter as detected by said plurality of tag transmission readers, so to locate said object within said environment.

2 more elements

A method for identifying locations of objects within a monitored environment, using time-of-arrival differentiation for a transmission from a tag disposed with one of said objects, as detected at a plurality of spaced apart tag transmission monitoring locations for said monitored environment comprising the steps of:

(a) transmitting from a tag transmitter coupled with a respective one of said objects a signal encoded with information representative of the identification of said object;
(b) at each of said plurality of spaced apart tag transmission monitoring locations, receiving said signal at a plurality of mutually diverse antennas;
(c) coupling signals received by said plurality of mutually diverse antennas to associated tag transmission readers which are operative to detect said signal transmitted by said tag transmitter;
(d) processing signals detected by said tag transmission readers and determine which signals received by said tag transmission readers are first-to-arrive signals as transmitted from said tag transmitter;
and
(e) conducting time-of-arrival differentiation processing of said first-to-arrive signals to locate said respective object within said environment.

3 more elements

Dependencies are inferred from the claim text.