초록 ▼

A short range radiolocation system and associated methods that allow the location of an item, such as equipment, containers, pallets, vehicles, or personnel, within a defined area. A small, battery powered, self-contained tag is provided to an item to be located. The tag includes a spread-spectrum t

A short range radiolocation system and associated methods that allow the location of an item, such as equipment, containers, pallets, vehicles, or personnel, within a defined area. A small, battery powered, self-contained tag is provided to an item to be located. The tag includes a spread-spectrum transmitter that transmits a spread-spectrum code and identification information. A plurality of receivers positioned about the area receive signals from a transmitting tag. The position of the tag, and hence the item, is located by triangulation. The system employs three different ranging techniques for providing coarse, intermediate, and fine spatial position resolution. Coarse positioning information is provided by use of direct-sequence code phase transmitted as a spread-spectrum signal. Intermediate positioning information is provided by the use of a difference signal transmitted with the direct-sequence spread-spectrum code. Fine positioning information is provided by use of carrier phase measurements. An algorithm is employed to combine the three data sets to provide accurate location measurements.

대표청구항 ▼

A short range radiolocation system and associated methods that allow the location of an item, such as equipment, containers, pallets, vehicles, or personnel, within a defined area. A small, battery powered, self-contained tag is provided to an item to be located. The tag includes a spread-spectrum t

A short range radiolocation system and associated methods that allow the location of an item, such as equipment, containers, pallets, vehicles, or personnel, within a defined area. A small, battery powered, self-contained tag is provided to an item to be located. The tag includes a spread-spectrum transmitter that transmits a spread-spectrum code and identification information. A plurality of receivers positioned about the area receive signals from a transmitting tag. The position of the tag, and hence the item, is located by triangulation. The system employs three different ranging techniques for providing coarse, intermediate, and fine spatial position resolution. Coarse positioning information is provided by use of direct-sequence code phase transmitted as a spread-spectrum signal. Intermediate positioning information is provided by the use of a difference signal transmitted with the direct-sequence spread-spectrum code. Fine positioning information is provided by use of carrier phase measurements. An algorithm is employed to combine the three data sets to provide accurate location measurements. meters. 5. A system as recited in claim 2, wherein said information processor estimates the parametric signal corresponding to a process parameter being monitored by one of said plurality of sensors. 6. A system as recited in claim 2, wherein said information processor determines a data acquisition failure associated with said sensor such that said data acquisition front-end is inhibited from providing the component signals from said sensor to said information processor, and wherein said information processor estimates the parametric signal corresponding to the component signals from said sensor in response to the data acquisition failure. 7. A system as recited in claim 5, wherein the data acquisition failure corresponds to a failure of said sensor, and said information processor determines the failure of said sensor. 8. A system as recited in claim 5, wherein the component signals from said sensor comprise a process parameter. 9. A system as recited in claim 1, wherein the one or more process parameters of the equipment correspond to physical operating characteristics including temperature, pressure, or displacement of the operational equipment being monitored. 10. An inferential signal generator, comprising: a memory for storing a set of time-correlated sensor data representative of expected operational states of a system selected from a process or a machine; a signal acquisition input for receiving sensor values from said system while in operation, descriptive of physical parameters of said system; a processor disposed to receive the sensor values from said signal acquisition input, and generate at least one output value descriptive of a parameter of the system that is not among parameters measured by the received sensor values, by comparing the similarity of the sensor values from said signal acquisition input to the set of sensor data in said memory. 11. An inferential signal generator as recited in claim 9, wherein said processor generates the at least one output value by a linear combination of the set of sensor data, adjusted according to said similarity of the sensor values to said set of sensor data. 12. An inferential signal generator as recited in claim 10, wherein the similarity of the sensor values from said signal acquisition input to the set of sensor data in said memory is measured by an element by element comparison of a numerical closeness of like sensor values with a full range of values for like sensors in said memory. 13. An inferential signal generator as recited in claim 10, wherein the set of sensory data in said memory comprises a plurality of snapshots of sensor data, each such snapshot comprising time-correlated values from the sensors on the system. 14. An inferential signal generator as recited in claim 12, wherein the sensor values received by said signal acquisition input from said system while in operation comprise a snapshot of time-correlated values from a subset of the sensors on the system. 15. An inferential signal generator as recited in claim 13, wherein said processor generates the at least one output value by a linear combination of the plurality of snapshots in said memory, adjusted according to said similarity of each such snapshot to the snapshot received by said signal acquisition input. 16. An inferential signal generator as recited in claim 9, wherein said signal acquisition input comprises a data bus electrically connected to sensors of said system. 17. An inferential signal generator as recited in claim 9, wherein said signal acquisition input comprises a wireless communications link disposed to receive transmissions containing the sensor values. 18. A control apparatus for a system selected from a process or machine, comprising: at least one actuator signal line connected to said system for conducting a control signal to said system; at least one sensor signal line connected to said system for conducting a signal from at least one sensor on said system indicative o