System and method for determining position of communicating devices

• US 20070133598A1
• Filed: 12/12/2005
• Published: 06/14/2007
• Est. Priority Date: 12/12/2005
• Status: Abandoned Application

• Current Assignee: Patrick Moran
• Original Assignee: Patrick Moran
• Inventors: Moran, Patrick
• Application Number:
  US11/299,456
• Publication Number:
  US 20070133598A1
• Time in Patent Office: Days
• US Class Current: 370/466
• CPC Class Codes: G01S 11/02 using radio waves G01S19/00 takes precedence
• CPC Class Codes: G01S 5/0289 of multiple transceivers, e.g. in ad hoc networks
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location

Abstract

The present invention determines distances between wireless sensor and computing nodes in a mesh computer or other network. The invention utilizes a set of sinusoidal waves, each being a multiple of a base frequency. The waves are transmitted from a first node to a second node. The second node determines the phase of the waves at the time of the zero-crossing in the first node. The distance between the nodes is determined based upon the phases. The waves may be sent as rotations of a quadrature signal.

Claims

1. A method for determining a distance between a first wireless communication device and a second wireless communication device, the method comprising the steps of:

transmitting a plurality of periodic signals from the first wireless communication device, wherein each of the plurality of signals has a frequency which is a multiple of a base frequency and wherein the plurality of signals are synchronized;

receiving the plurality of periodic signals at the second wireless communication device;

determining a phase of each of the plurality of periodic signals at a synchronized time; and

determining the distance between the first wireless communication device and the second wireless communication device based upon the determined phases of the plurality of periodic signals.

2. The method according to claim 1, wherein the plurality of periodic signals include a plurality of sinusoidal signals.

3. The method according to claim 1, wherein one of the plurality of signals has a frequency corresponding to the base frequency.

4. The method according to claim 3, wherein the plurality of periodic signals includes periodic signals having frequencies at integer powers of 2 of the base frequency.

5. The method according to claim 1, wherein the synchronized time includes a starting time of a signal at the base frequency.

6. The method according to claim 2, wherein the synchronization time includes a zero crossing time of a signal at the base frequency.

7. The method according to claim 1, wherein the transmitting steps includes transmitting the plurality of periodic signals in a time multiplexed format.

8. The method according to claim 1, further comprising the steps of:

transmitting a second plurality of periodic signals from the second wireless communication device; and

receiving the second plurality of periodic signals at the first wireless communication device; and

wherein the step of transmitting the plurality of periodic signals includes transmitting the plurality of periodic signals in phase with the received second plurality of periodic signals.

9. The method according to claim 1, wherein the plurality of periodic signals are transmitted as angular values of a signal having quadrature components.

10. The method according to claim 1, wherein the plurality of periodic signals are superimposed on communications signals between the first wireless communication device and the second wireless communication device.

12. The system according to claim 1, wherein:

the second wireless communication device further includes;

a second signal generator generating and transmitting a second plurality of periodic signals, wherein each of the second plurality of signals has a frequency which is a multiple of a base frequency and wherein the second plurality of signals are synchronized;

the first wireless communication device further includes a receiver for receiving the second plurality of periodic signals; and

the signal generator of the first wireless communication device generates the plurality of periodic signals as in phase replicas of the second plurality of periodic signals.

11. A system for determining distances comprising:

a first wireless communication device including;

a signal generator for generating and transmitting a plurality of periodic signals, wherein each of the plurality of signals has a frequency which is a multiple of a base frequency and wherein the plurality of signals are synchronized;

a second wireless communication device including;

a receiver for receiving the plurality of periodic signals;

a signal processor for determining a phase of each of the plurality of periodic signals at a synchronized time; and

a distance processor for determining the distance between the first wireless communication device and the second wireless communication device based upon the determined phases of the plurality of periodic signals.

13. A system for determining a position of a first node in a wireless network, the system comprising:

a plurality of known nodes, wherein each of the known nodes has a stored position and wherein each of the known nodes includes;

a signal generator for generating and transmitting a plurality of periodic signals, wherein each of the plurality of signals has a frequency which is a multiple of a base frequency and wherein the plurality of signals are synchronized; and

a transmitter for transmitting the stored position; and

wherein the first node includes;

a receiver for receiving the plurality of periodic signals from each of the plurality of known nodes and the transmitted stored positions;

a signal processor for determining a phase of each of the plurality of periodic signals at a synchronized time;

a distance processor for determining the distance between the first node and each of the plurality of known nodes based upon the determined phases of the plurality of periodic signals; and

a position processor for determining position based upon the received stored positions and the determined distances.

14. The system for determining position of a first node in a wireless network according to claim 13, wherein at least one of the plurality of known nodes includes a GPS system for determining a position as the stored position.

15. The system for determining position of a first node in a wireless network according to claim 13, wherein at least one of the plurality of known nodes includes an input for receiving an entered position as the stored position.