Signal Comparison-Based Location Determining Method

• US 20080070572A1
• Filed: 09/19/2006
• Published: 03/20/2008
• Est. Priority Date: 09/19/2006
• Status: Active Grant

• Current Assignee: Broadphone, LLC
• Original Assignee: Broadphone, LLC
• Inventors: Shkedi, Roy
• Granted Patent: US 7,706,811 B2
• Time in Patent Office: Days
• US Class Current: 455/435.1
• CPC Class Codes: G01S 5/02521 using a radio-map
• CPC Class Codes: H04W 4/023 using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds

Abstract

At least one portable RF communications device in conjunction with at least two fixed-location service-area antenna stations respectively capable of RF communication with the at least one device performs the steps of: (I) using a portable device at a selected location to measure RF communications signals from the plurality of local fixed-location service-area antenna stations and electronically storing at least two of the respective reception signal strength measurements; and (II) monitoring a portable device location by causing the device to measure reception signal strength associated with local fixed-location service-area antenna stations signals, and to electronically compare these measurements with the stored at least two measurements.

Claims

1. A Signal-Comparison Based Location-Determining Method, operable by at least one portable RF communications device in conjunction with at least two fixed-location service-area antenna stations respectively capable of RF communication with the at least one device wherein the stations are substantially continuously operating, and the method is comprising the steps of:

(A) Registering a selected location by first-causing a portable RF communications device at the selected location

(i) to receive an RF communications signal from a plurality of local fixed-location service-area antenna stations, and

(ii) to measure reception signal strength respectively associated with the received signal from at least two of the plurality of antenna stations;

(B) Recording the selected location by electronically storing at least two of the respective reception signal strength measurements;

(C) Monitoring by second-causing a portable RF communications device

(i) to receive communications signals from a plurality of respectively local fixed-location service-area antenna stations, and

(ii) to measure reception signal strength associated with the signals; and

(D) Determining if the portable RF communications device of the Monitoring step is at the selected location of the registering step by electronically comparing measurements in the monitoring step with the stored at least two measurements of the Recording step.

2. The Signal-Comparison Based Location-Determining Method according to claim 1 wherein the Registering step includes identifying at least one ID within at least one of the respectively received signals;

and the Recording step includes storing each of the at least one IDs with the respective reception signal strength measurement.

3. The Signal-Comparison Based Location-Determining Method according to claim 2 wherein the Monitoring step includes identifying at least one ID within at least one of the respectively received signals and the Determining step includes electronically matching at least one ID of the Monitoring step with the stored at least one ID of the Recording step.

4. The Signal-Comparison Based Location-Determining Method according to claim 1 wherein the Monitoring step includes iteratively performing the sub-steps C.i and C.ii with a predetermined time delay between successive iterations of C.i such that the monitoring step data is used only if a substantial portion of the successive C.ii measurements are alike within a predetermined threshold—

since this indicates that the portable RF device of step C is temporally immobile.

5. The Signal-Comparison Based Location-Determining Method according to claim 1 wherein the Determining step includes improving the electronically stored at least two of the respective reception signal strength measurements of step B by storing at least one measurement of step C therewith—

thereby upgrading robustness of the electronically stored measurements.

6. The Signal-Comparison Based Location-Determining Method according to claim 1 wherein the Registering step includes accessing a GPS location coordinate for the selected location and Recording step includes keeping the GPS location coordinate with the stored signal strength measurements.

7. The Signal-Comparison Based Location-Determining Method according to claim 1 wherein the Registering step includes directly transferring the measurements within the portable RF communications device to a storage module therein whereat the Recording step is preformed.

8. The Signal-Comparison Based Location-Determining Method according to claim 1 wherein the Registering step includes, via RF communications, transferring the measurements from the portable RF communications device to a storage device whereat the Recording step is preformed;

and wherein the Recording step includes, via RF communications, receiving the measurements.

9. The Signal-Comparison Based Location-Determining Method according to claim 1 wherein the Determining step includes calculating a confidence metric according to a degree of correlation between the measurements in the Monitoring step with the stored at least two measurements of the recording step.

10. A Signal-Comparison Based Location-Determining Database recorded on a tangible memory media and having recorded thereon signal-strength location correlation data deriving from the Registering step or the Monitoring step of the Signal-Comparison Based Location-Determining Method according to claim 1.

11. An article of manufacture including a computer usable medium having computer readable program code embodied therein for Signal-Comparison Based Location-Determining, the computer readable program code in said article of manufacture including:

first computer readable program code for causing a computer to to Register a selected location by first-causing a portable RF communications device at the selected location

(i) to receive an RF communications signal from a plurality of local fixed-location service-area antenna stations, and

(ii) to measure reception signal strength respectively associated with the received signal from at least two of the plurality of antenna stations;

tied to the first computer readable software, second computer readable program code for causing the computer to Record the selected location by electronically storing at least two of the respective reception signal strength measurements;

tied to the second computer readable software, third computer readable program code for causing the computer to Monitor by second-causing a portable RF communications device

(i) to receive communications signals from a plurality of respectively local fixed-location service-area antenna stations, and

(ii) to measure reception signal strength associated with the signals; and

tied to the third computer readable software, fourth computer readable program code for causing the computer Determine if the portable RF communications device of the Monitoring step is at the selected location of the registering step by electronically comparing measurements in the monitoring step with the stored at least two measurements of the Recording step.

12. A Signal-Comparison Based Location-Determining Method, operable by at least one portable RF communications device in conjunction with at least two fixed-location service-area antenna stations respectively capable of RF communication with the at least one device wherein the stations are substantially continuously operating, and the method is comprising the steps of:

(A) First-Causing a portable RF communications device at a selected location to receive an RF communications signal from a plurality of local fixed-location GSM service-area antenna stations;

(B) First-Measuring reception signal strength respectively associated with the “

First-Causing”

received signal from at least two of the plurality of antenna stations;

(C) Second-Causing a portable RF communications device to receive an RF communications signal from a plurality of local fixed-location GSM service-area antenna stations;

(D) Second-Measuring reception signal strength respectively associated with the “

Second-Causing”

received signals; and

(E) Determining, if the portable RF communications device of the “

Second-Causing”

step is at the selected location of the “

First-Causing”

step, By electronically Comparing at least two of the respective reception signal measurements of the “

First-Measuring”

step with at least two of the respective reception signal measurements of the “

Second-Measuring”

step.

13. A Signal-Comparison Based Location-Determining Method, operable by at least one portable RF communications device in conjunction with at least two fixed-location service-area antenna stations respectively capable of RF communication with the at least one device wherein the stations are substantially continuously operating, and the method is comprising the steps of:

(A) First-Causing a portable RF communications device at a selected location to receive an RF communications signal from a plurality of local fixed-location CDMA service-area antenna stations;

(B) First-Measuring reception signal strength respectively associated with the “

First-Causing”

received signal from at least two of the plurality of antenna stations and therewith calculating respectively relative signal reception strengths;

(C) Second-Causing a portable RF communications device to receive an RF communications signal from a plurality of local fixed-location CDMA service-area antenna stations;

(D) Second-Measuring reception signal strength respectively associated with the “

Second-Causing”

received signals and therewith calculating respectively relative signal reception strengths; and

(E) Determining, if the portable RF communications device of the “

Second-Causing”

step is at the selected location of the “

First-Causing”

step, By electronically Comparing at-least one of the calculated respective relative reception signal strengths of the “

First-Measuring”

step with at-least one of the calculated respective relative reception signal strengths of the “

Second-Measuring”

step.

14. A Signal-Comparison Based Location-Determining system, substantially as herein before described and illustrated, and characterized by using interconnected software enabled modules on at least one portable RF communications device, said modules operating in conjunction with at least two fixed-location service-area antenna stations that are respectively capable of RF communication with the at least one device wherein the stations are substantially continuously operating, and these software modules include:

(A) a registration module for Registering a selected location by first-causing a portable RF communications device at the selected location

(i) to receive an RF communications signal from a plurality of local fixed-location service-area antenna stations, and

(ii) to measure reception signal strength respectively associated with the received signal from at least two of the plurality of antenna stations;

(B) a recording module for Recording the selected location by electronically storing at least two of the respective reception signal strength measurements;

(C) a monitoring module Monitoring by second-causing a portable RF communications device

(i) to receive communications signals from a plurality of respectively local fixed-location service-area antenna stations, and

(ii) to measure reception signal strength associated with the signals; and

(D) a determination module for Determining if the portable RF communications device of the Monitoring step is at the selected location of the registering step by electronically comparing measurements in the monitoring step with the stored at least two measurements of the Recording step.