Method and system for determining the speed and distance of a mobile unit

• US 20040203905A1
• Filed: 12/27/2002
• Published: 10/14/2004
• Est. Priority Date: 06/28/2002
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Cuffaro, Angelo
• Granted Patent: US 7,123,924 B2
• Time in Patent Office: Days
• US Class Current: 455/456.1
• CPC Class Codes: G01S 11/02 using radio waves G01S19/00 takes precedence
• CPC Class Codes: G01S 11/04 using angle measurements
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station
• CPC Class Codes: G01S 5/02 using radio waves using satellite radio beacon systems for determining position G01S19/00
• CPC Class Codes: G01S 5/12 by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 64/006 with additional information processing, e.g. for direction or speed determination

Abstract

A method and system where a common channel (such as a beacon channel) is swept over a specified coverage area of a sectorized cell is disclosed. An idle WTRU saves pertinent information such as received power and time of reception of the last several readings of the common channel. On the WTRU'"'"'s next access, the information is sent to the network to determine the WTRU'"'"'s location, its direction of travel and a speed estimate which is valuable for radio resource management.

Claims

1. A communications system having a plurality of wireless transmit receive units (WTRUs), the system comprising:

a receiver that is configured to monitor a selected channel while in an idle state;

a memory to store information regarding the selected channel;

a transmitter to send the stored information from the WTRU at an appropriate time; and

means to calculate a speed and distance of each of the plurality of WTRUs using the stored information.

2. The communications system of claim 1, wherein the sending step further comprises sending information from a previous three WTRU accesses.

3. The communications system of claim 1, wherein the information includes at least one of the following:

pathloss, sector identification, power and time of acquisition.

4. The communications system of claim 1, wherein the common channel includes a unique sector identifier.

5. The communications system of claim 3, wherein the pathloss is determined from a rural or a suburban environmental factor.

6. The communications system of claim 1, wherein the distance is calculated in accordance with a cost-231 Hata model.

7. The communications system of claim 1, wherein the distance is calculated in accordance with a plane earth propagation model.

8. The communications system of claim 1, wherein the distance is calculated in accordance with a free space model.

9. A method for determining the speed, direction and distance of a WTRU which traverses one or more sectors, each sector having at least one common channel, the method comprising:

monitoring the at least one channel of each traversed sector while in an idle state;

storing information regarding each beacon channel;

sending the stored information from the WTRU at an appropriate time; and

using triangulation and the information to calculate the speed and distance of the WTRU.

10. The method of claim 9 wherein the sending step further comprises sending information from at least three previous WTRU accesses.

11. The method of claim 9 wherein the information includes at least one of the following:

path loss, sector identification, power and time of acquisition.