Radio frequency environment object monitoring system and methods of use

• US 8,599,024 B2
• Filed: 01/17/2012
• Issued: 12/03/2013
• Est. Priority Date: 02/27/2009
• Status: Active Grant

• Current Assignee: RF Controls LLC
• Original Assignee: RF Controls LLC
• Inventors: Bloy, Graham P.
• Primary Examiner(s): MCNALLY, KERRI L
• Application Number:
  US13/351,971
• Publication Number:
  US 20120112913A1
• Time in Patent Office: 686 Days
• Field of Search: 340/539.13, 340/572.1
• US Class Current: 340/572.1
• CPC Class Codes: G01S 13/003 Bistatic radar systems; Multistatic radar systems
• CPC Class Codes: G01S 13/04 Systems determining presence of a target based on relative movement of target G01S13/56
• CPC Class Codes: G01S 13/758 using a signal generator powered by the interrogation signal
• CPC Class Codes: G01S 13/82 wherein continuous-type signals are transmitted
• CPC Class Codes: G01S 13/872 Combinations of primary radar and secondary radar
• CPC Class Codes: G01S 2013/0245 Radar with phased array antenna
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders

Abstract

A method and apparatus for monitoring untagged objects in a target area including calibrating a radio environment monitoring system including a rules engine and a baseline data set for a target area by recording a set of changes to the RF environment fingerprint of the target area received by the radio environment monitoring system as the target area is filled with objects. During system operation, scanning the target area with the radio environment monitoring system for a current RF environment fingerprint, comparing the current RF environment fingerprint with the baseline data set by a rules engine and reporting an output of the rules engine.

Claims

1. A radio frequency environment object monitoring system, comprising:

a three dimensional radio environment monitoring system, comprising

an RF transmitter-receiver coupled to an antenna, the antenna provided with an electronic steering circuit;

the antenna operative to launch a continuous wave signal, the continuous wave signal steerable by the electronic steering circuit;

a processor provided with a data matrix for storing a plurality of signal data records of a plurality of response signal(s) received by the RF transmitter-receiver; and

a position logic operative upon the data record(s) to derive a three dimensional signal origin location of the plurality of response signals within a target area;

a baseline data set of the response signals associated with known object locations within the target area, prior to entry into the target area of untagged objects;

the plurality of response signals including an RF environment fingerprint, the RF environment fingerprint including;

a fast Fourier transform (FFT) of a received signal envelope at an instant in time; and

a time reference;

and

a rules engine for comparing the signal data record(s) with the baseline data set to determine an object inventory.

2. The system of claim 1, wherein the three dimensional radio environment monitoring system is an intelligent tracking and control system.

3. The system of claim 1, wherein the three dimensional radio environment monitoring system includes at least two RF transmitter-receivers and antennas.

4. A method for monitoring untagged objects in a target area, comprising the steps of:

calibrating a three dimensional radio environment monitoring system for a target area by recording a baseline data set of changes to an RF environment fingerprint of the target area received by the three dimensional radio environment monitoring system as the target area is filled with objects;

the RF environment fingerprint including;

a fast Fourier transform (FFT) of a received signal envelope at an instant in time; and

a time reference;

scanning the target area with the three dimensional radio environment monitoring system for a current RF environment fingerprint;

comparing the current RF environment fingerprint with the baseline data set of changes to the RF environment fingerprint of the target area received by the three dimensional radio environment monitoring system as the target area was filled with objects by a rules engine; and

reporting an output of the rules engine.

5. The method of claim 4, wherein the baseline data set includes changes to the RF environment fingerprint caused by filling the target area with multiple objects in multiple positions within the target area.

6. The method of claim 4, wherein the rules engine includes a line of sight parameter wherein a degradation of a signal response from a reference RFID in the target area indicates the presence of an object along a line of sight between the reference RFID and an antenna associated with the signal response.

7. The method of claim 4, wherein the rules engine includes a dynamic pseudo emitter parameter wherein a pseudo emitter that appears and or disappears correlates to an object being positioned at a known location according to the baseline data set.

8. The method of claim 4, wherein the rules engine includes a static pseudo emitter parameter wherein a signal degradation of a static pseudo emitter correlates to an object being positioned at a known location according to the baseline data set.

9. The method of claim 4, wherein the rules engine output is an inventory report indicating that an inventory of an object has fallen below a preset amount.

10. The method of claim 4, wherein the rules engine output is coupled to an electronic stock keeping system that issues a purchase order for an object that has fallen below a preset amount.

11. The method of claim 4, wherein the RF environment fingerprint is averaged from multiple scans of the target area.

12. The method of claim 4, wherein each of a plurality of records of the baseline data set is averaged from multiple scans of the target area during a static object condition.

13. The method of claim 4, wherein the appearance in the RF environment fingerprint of a registered reference RFID(s) indicates a change to the target area access.

14. The method of claim 13, wherein the change to the target area access is the opening of a door.

15. The method of claim 4, wherein the rules engine applies a probability factor to an object presence determination.

16. The method of claim 15, wherein the rules engine only outputs object presence determinations that have a probability factor above a preset level.

17. The method of claim 4, wherein objects with RFID tags are included as sources of reference RFID tags during RF environment fingerprint monitoring.