Enhanced dead reckoning method

• US 20040230374A1
• Filed: 05/12/2003
• Published: 11/18/2004
• Est. Priority Date: 05/12/2003
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Dash Navigation, Inc.
• Inventors: Tzamaloukas, Assimakis
• Granted Patent: US 7,076,365 B2
• Time in Patent Office: Days
• US Class Current: 701/217
• CPC Class Codes: G01C 21/28 with correlation of data from several navigational instruments

Abstract

An enhanced dead reckoning method determines the position of a participating vehicle. The participating vehicle is unable to receive signals from global positioning satellites. The position is calculated by way of observed time difference calculations and received signal strength indications. The position is also calculated by communicating with other participating vehicles or egress points.

Claims

1. An enhanced dead reckoning method for determining the position of a participating vehicle, wherein the participating vehicle is operative to communicate with at least one egress point, the method comprising:

(a) calculating a first position of the participating vehicle by way of an observed time difference calculation;

(b) calculating a second position of the participating vehicle by way of a received signal strength indication;

(c) determining the position of the participating vehicle from the first position and the second position.

2. The invention of claim 1 wherein said calculating in (a) is performed at the participating vehicle.

3. The invention of claim 1 wherein said calculating in (a) is performed at the at least one egress point.

4. An enhanced dead reckoning method for determining the position of a participating vehicle, wherein the participating vehicle is operative to communicate with other participating vehicles according to an enhanced ad-hoc mode of communications and wherein the participating vehicle is operative to communicate with at least one egress point of the transportation network, the method comprising:

(a) calculating a first position of the participating vehicle by way of an observed time difference calculation with the at least one egress point;

(b) calculating a second position of the participating vehicle by communicating with the other participating vehicles;

(c) determining the position of the participating vehicle from the first position and the second position.

5. An enhanced dead reckoning method for determining the position of a participating vehicle, wherein the participating vehicle is operative to communicate with other participating vehicles, according to an enhanced ad-hoc mode of communications, wherein the positions of at least some of the other participating vehicles are known according to global positioning system measurements, the method comprising:

(a) receiving from the other participating vehicles the positions of at least some of the other participating vehicles;

(b) determining the position of the participating vehicle from the positions received in (a).

6. An assisted global positioning system method for determining the position of a participating vehicle, wherein the participating vehicle is operative to communicate with an apparatus, wherein the position of apparatus is ascertained according to a global positioning system, the method comprising:

(a) determining a first position of the participating vehicle according to a dead reckoning method;

(b) transmitting the first position to the apparatus;

(c) receiving from the apparatus location and correction information;

(d) determining the position of the participating vehicle by applying the location and correction information received in (c) to the first position.

7. The invention of claim 6 wherein the apparatus is an egress point.

8. The invention of claim 6 wherein the apparatus is another participating vehicle.