Location of cooperative tags with personal electronic device

• US 7,917,155 B2
• Filed: 10/25/2007
• Issued: 03/29/2011
• Est. Priority Date: 10/27/2006
• Status: Active Grant

• Current Assignee: Santa Mionica Semiconductor
• Original Assignee: RoundTrip, LLC
• Inventors: Mankovitz, Roy J., Karr, Lawrence J.
• Primary Examiner(s): Le; Danh C
• Application Number:
  US11/924,553
• Publication Number:
  US 20080102859A1
• Time in Patent Office: 1,251 Days
• Field of Search: 455/456.1, 455/556.1, 455/418, 340/10.1, 375/343
• US Class Current: 455/456.1
• CPC Class Codes: G01S 13/825 with exchange of information between interrogator and responder
• CPC Class Codes: G01S 5/0284 Relative positioning
• CPC Class Codes: G08B 21/0227 System arrangements with a plurality of child units
• CPC Class Codes: G08B 21/023 Power management, e.g. system sleep and wake up provisions
• CPC Class Codes: G08B 21/0263 System arrangements wherein the object is to detect the direction in which child or item is located
• CPC Class Codes: G08B 21/0266 System arrangements wherein the object is to detect the exact distance between parent and child or surveyor and item
• CPC Class Codes: G08B 21/0272 System arrangements wherein the object is to detect exact location of child or item using triangulation other than GPS
• CPC Class Codes: G08B 21/24 Reminder alarms, e.g. anti-loss alarms
• CPC Class Codes: H04W 4/025 using location based information parameters

Abstract

The present disclosure relates to location and communication systems that can be utilized for locating people, pets and other objects with a software defined radio set. A personal electronic device (PED) such as a cellular telephone, personal data assistant (PDA) or other device that include a software defined radio set can be configured for operation as a locator device. The PED transmits a signal A transponder or micro-transponder (MT) that is tagged to an object is arranged to reply to a transmission received from the PED. The PED based locator is arranged to calculate a distance between the PED and the MT using the time-of-flight (TOF) between the transmission and the receipt of a reply. The absolute geographic position of the PED can be determined using satellite navigation information, while the position of the MT relative to the PED can be determined from the TOF information.

Claims

1. A method for determining the relative position of a cooperative transponder by the use of a software defined radio transceiver in a personal electronic device, wherein the primary function of the software defined radio set is that of a cellular telephone, the method comprising:

receiving a user initiated input that is indicative of a mode selection to a locator mode in the personal electronic device;

executing a radio set configuration logic with a processor in the personal electronic device such that the processor reconfigures the software defined radio transceiver from a cellular telephone mode to a locator mode, wherein the software defined radio set and the processor in the personal electronic device are arranged to operate the locator mode by;

selecting a target ID associated with the cooperative transponder;

coding a sequence for the selected target ID;

initiating the transmission of a structured multi-frame transmission to the cooperative transponder over a first time interval with the software defined radio set;

capturing sample of a signal spectrum over a second time interval that is subsequent to the first time with the software defined radio set;

correlating the captured samples over a third time interval with the software defined radio set;

detecting a valid reply from the cooperative transponder device when the captured samples correlate to a structured reply transmission from the cooperative transponder with a reply cadence and frequency that substantially matches the expected reply cadence and frequency based on the internal clock of the personal electronic device; and

determining a round-trip time-of-flight between the transmission of the structure multi-frame transmission and the detected valid reply.

2. The method of claim 1, wherein the personal electronic device is further arranged to operate the locator mode by:

determining the absolute geographic position of the personal electronic device with a satellite navigation system that is resident in the personal electronic device, determining the velocity of the personal electronic device with the satellite navigation system, and determining the absolute geographic position of the cooperative transponder from the determined absolute geographic position and determined velocity of the personal electronic device.

3. The method of claim 1, further comprising:

determining a relative position of the cooperative transponder with the round-trip time-of-flight measurement and a Doppler shift measurement that is calculated by the personal electronic device.

4. The method of claim 1, further comprising:

determining a relative position of the cooperative transponder with the round-trip time-of-flight measurement and an interferometric measurement that is calculated by the personal electronic device.

5. The method of claim 2, wherein determining the absolute geographic position of the cooperative transponder further comprises calculating a relative position of the cooperative transponder with the round-trip time-of-flight and a Doppler shift measurement, and identifying the absolute geographic position of the cooperative transponder from the absolute geographic position of the personal electronic device and the relative position of the cooperative transponder.

6. The method of claim 2, wherein determining the absolute geographic position of the cooperative transponder further comprises calculating a relative position of the cooperative transponder with the round-trip time-of-flight measurement and an interferometric measurement, and identifying the absolute geographic position of the cooperative transponder from the absolute geographic position.

7. The method of claim 1, further comprising activating the locator mode for the personal electronic device from a speech input.

8. The method of claim 1, wherein selecting the target ID associated with the cooperative transponder comprises at least one member of the list comprising selecting the target ID from a speech input from the user, selecting the target ID from a text input from the user, or selecting the target ID from a directory list of target objects.

9. The method of claim 1, wherein the personal electronic device is further arranged to operate the locator mode by:

accessing a frequency standard from satellite navigation system that is resident in the personal electronic device, and reducing a frequency and time uncertainty in the location process with the frequency standard.

10. The method of claim 1, further comprising:

determining a position associated with the cooperative transponder by transmitting a location request to additional personal electronic devices whose primary function is that of a cellular telephone, where the location request includes the target ID associated with the cooperative transponder, and receiving location information for the cooperative transponder associated with the target ID from the additional personal electronic devices.

11. The method of claim 10, where each additional personal electronic device is arranged to report the relative position of the cooperative transponder.

12. The method of claim 10, where each additional personal electronic device is arranged to report the absolute geographic position of the cooperative transponder.

13. The method of claim 10, where each additional personal electronic device is arranged to relay position information from another additional personal electronic device.

14. The method of claim 1, further comprising:

receiving a location request from another personal electronic device whose primary function is that of a cellular telephone, identifying the target ID for the cooperative tag from the location request, and transmitting a location determination for the cooperative tag identified by the location request to the another personal electronic device.