Distance separation tracking system

• US 8,823,577 B2
• Filed: 12/21/2010
• Issued: 09/02/2014
• Est. Priority Date: 12/23/2009
• Status: Active Grant

• Current Assignee: Hailo Technologies, LLC (2S Ventures, LLC)
• Original Assignee: iTrack LLC
• Inventors: Smid, G. Edzko, Stiglich, Thomas P.
• Primary Examiner(s): BYTHROW, PETER M
• Application Number:
  US12/974,672
• Publication Number:
  US 20110148710A1
• Time in Patent Office: 1,351 Days
• Field of Search: 342/27, 342/42, 342/44, 342/51, 342/118, 342/126, 342/127, 342/146, 342/147, 342/175, 342/378, 342/450, 342/451, 342/458, 342/461, 342/463, 342/464, 342/465, 340/539.1, 340/539.11, 340/539.13, 340/539.14, 340/539.15, 340/568.1, 340/573.1, 340/686.6
• US Class Current: 342/42
• CPC Class Codes: G01S 13/46 Indirect determination of position data
• CPC Class Codes: G01S 13/84 for distance determination by phase measurement
• CPC Class Codes: G01S 2013/466 by Trilateration, i.e. two antennas or two sensors determine separately the distance to a target, whereby with the knowledge of the baseline length, i.e. the distance between the antennas or sensors, the position data of the target is determined

Abstract

A distance separation tracking process is provided that includes the transmission of a periodic radio frequency original signal from a beacon transceiver. The original periodic signal from the beacon transceiver is received at a remote target transceiver as a target received periodic signal. The target retransmits the received periodic signal to the beacon transceiver as a return periodic signal. Data points of the return periodic signal are sampled and used to calculate a phase differential between the original periodic signal and the return periodic signal that correlates to the distance separation range between the beacon transceiver and the target transceiver.

Claims

1. A distance separation tracking process comprising:

transmitting a periodic radio frequency original signal from a beacon transceiver as a signal packet as a disruption on an audio channel of a radio system to provide the distance separation tracking capability, said original signal being defined by a mathematical equation;

receiving the original periodic signal from said beacon transceiver at a remote target transceiver as a target received periodic signal;

conveying the target received periodic signal to a transmitter within said target transceiver by way of a hardwired loop connect;

retransmitting the target received periodic signal to said beacon transceiver as a return periodic signal;

sampling data points of said return periodic signal, a receiver in said beacon transceiver providing a signal strength measurement for said return periodic signal directly to a microprocessor in said beacon transceiver;

calculating a phase differential between the original periodic signal and the returned periodic signal correlating to a distance separation range between said beacon transceiver and said target transceiver based on the signal strength measurements without adjusting a gain loop of the receiver; and

wherein said distance separation is determined in spite of intermediate obstructions and without reliance on GPS, clock synchronization, or line of sight.

2. The process of claim 1 wherein said return periodic signal is sampled for a duration to yield between 100 and 10,000 of said data points.

3. The process of claim 2 wherein the frequency of said periodic original signal is between 10 and 2400 kiloHertz.

4. The process of claim 1 wherein the calculated phase differential between the periodic original signal and the return periodic signal is derived from each of the sampling data points by at least one of average or medium, regression fitting, combinatorial optimization, random optimization, stochastic approximation routines, and quadratic optimization routines.

5. The process of claim 1 wherein the periodic original signal is a sine wave.

6. The process of claim 1 wherein the periodic original signal is an amplitude modulation signal.

7. The process of claim 1 wherein said beacon transceiver transmits the periodic original signal on a first channel and receives the returned periodic signal on a second channel.

8. The process of claim 1 wherein sampling data points of the returned periodic signal occurs at a sampling rate at least twice the frequency of the original signal.

9. The process of claim 1 wherein data points associated with extrema of the returned periodic signal are discarded prior to calculating the distance separation range from the data points.

10. The process of claim 1 further comprising applying an error band to the data points to discard those data points with an error between the periodic original signal and the return signal beyond a preselected band prior to calculating the distance separation range therefrom.

11. The process of claim 10 further comprising applying an average filter to the distance separation range calculated.

12. The process of claim 11 further comprising using the average filter to modify the extent of said error band.