Mobile phone enhanced cell coverage determining method and system for same

• US 6,853,845 B2
• Filed: 08/15/2001
• Issued: 02/08/2005
• Est. Priority Date: 07/23/2001
• Status: Active Grant

• Current Assignee: Far Eastone Telecommunications Company Limited, Riti Taiwan, Inc.
• Original Assignee: Far Eastone Telecommunications Company Limited, Riti Taiwan, Inc.
• Inventors: Ran, Saint-Yue, Hsu, Ching-Hsiang
• Primary Examiner(s): Trost, William
• Assistant Examiner(s): Le, Danh C
• Application Number:
  US09/930,610
• Publication Number:
  US 20030017829A1
• Time in Patent Office: 1,273 Days
• Field of Search: 455/449, 455/444, 455/446, 455/443, 455/561, 455/562.1, 455/456.6, 370/328, 370/329, 370/334, 370/336, 370/339, 343/757, 343/878, 343/879
• US Class Current: 455/449
• CPC Class Codes: H04W 16/18 Network planning tools

Abstract

This is a method and system for determining an enhanced cell coverage locating a mobile terminal in a cellular mobile communication system. The overall range of the mobile communication system is divided into a plurality of pixels, and then a pixel map including all pixels is constructed. One antenna with a shortest distance to each pixel is set as a serving antenna, and the nearest antenna to a pixel is found. This pixel then belongs to the cell of this antenna, in which the distance therebetween is smallest and all pixels belonging to a cell constitutes a pixel coverage of this cell. A rectangular area is then constructed covering the pixel coverage, and a smallest circle cover this rectangular area is constructed as the enhanced cell coverage of the antenna. Thereby, the system provider may provide require information to the mobile terminal in that coverage.

Claims

1. A method for determining an enhanced cell coverage in a mobile communication system having a plurality of mobile terminals, a plurality of base stations each including at least one antenna, and a cell database containing the relationship between a plurality of cells, the plurality of base stations, and the antennas, the mobile communication system having a communication system coverage for receiving signals and each of the antennas having an antenna coverage for receiving signals, wherein the communication system coverage is divided into a plurality of unit sections, the method comprising the steps of:

(1.1) designating each one of the plurality of unit sections to be associated with an antenna of one of said plurality of base stations for each of the antennas, said designation being responsive to the shortest distance from a unit section to an antenna, said shortest distance being determined in comparison with the distance from a unit section to all the other antennas in the communication system; and

(1.2) forming a plurality of enhanced cell coverages of said antenna of said base station, wherein said plurality of enhanced cell coverages includes all of the plurality of said designated unit sections for all of the antennas in the communication system.

2. The method of claim 1, wherein said step (1.1) further comprises steps of:

(2.1) classifying each of said plurality of antenna coverages as outdoor macro cells, outdoor micro cells and indoor micro cells, said classification responsive to the covering range, antenna directivity and traffic of said antenna;

(2.2) dividing said communication system coverage into a plurality of pixels;

(2.3) constructing a pixel map comprising all of the locations of said plurality of pixels;

(2.4) determining the distances between each of said plurality of pixels and its nearest proximate antenna;

(2.5) determining which one of the antennas has the shortest distance to a selected pixel, said antenna being a serving antenna of said selected pixel;

(2.6) constituting a pixel coverage of said serving antenna by selecting all of said pixels having a shortest distance to said serving antenna;

(2.7) constructing a rectangular area covering said pixel coverage; and

(2.8) constructing a circle having a center being the intersecting point of the diagonal lines of said rectangular area and a radius of one-half of said diagonal line.

3. The method of claim 2, wherein said step (2.6) further comprises a step of removing from said pixel map those pixel coverages in which a predetermined small number of mobile terminals are located.

4. The method of claim 2, wherein said step (2.4) further comprises a step of repositioning a location of an antenna to be away from an original location of said antenna with a distance of one-half of a maximum size of a pixel.

5. The method of claim 2, wherein said step (2.8) further comprises a step of setting a radius to be zero responsive to said cell being an indoor micro cell.

6. The method of claim 2, wherein said step (2.7) further comprises a step of designating a maximum longitudinal extent of said pixel coverage to be a length of said rectangular area, and designating a maximum transversal extent of said pixel coverage to be a width of said rectangular area.

7. The method of claim 1, wherein the mobile communication system is a time-division multiple access mobile communication system.

8. The method of claim 7, wherein the time-division multiple access mobile communication system is a digital GSM system.

9. A method for determining an enhanced cell coverage in a mobile communication system having a plurality of mobile terminals, a plurality of base stations each including at least one antenna, and a cell database containing the relationship between a plurality of cells, the plurality of base stations, and the antennas, the mobile communication system having a communication system coverage for receiving signals and each of the antennas having an antenna coverage for receiving signals, wherein the communications system coverage is divided into a plurality of unit sections, the method comprising the steps of:

(9.1) designating one of the plurality of unit section to be associated with an antenna of one of the plurality of base stations for each of the antennas, said designation being responsive to the shortest distance from said unit section to said antenna, said shortest distance being determined in comparison with all the other antennas in the communication system, and forming a first enhanced cell coverage of said antenna of the base station, wherein said first enhanced cell coverage includes all of the unit sections having a shortest distance to said antenna;

(9.2) forming a second enhanced cell coverage responsive to the time advance method of the mobile communication system; and

(9.3) selecting a minimum from said first enhanced cell coverage and said second enhanced cell coverage as an enhanced cell coverage of the antenna of said base station.

10. The method of claim 9, wherein said step (9.1) further comprises steps of:

(10.1) classifying each of said plurality of antenna coverages as outdoor macro cells, outdoor micro cells and indoor micro cells, said classification responsive to the covering range, antenna directivity and traffic of said antenna;

(10.2) dividing said communication system coverage into a plurality of pixels;

(10.3) constructing a pixel map comprising all of the locations of said plurality of pixels;

(10.4) determining the distances between each of said plurality of pixels and its nearest proximate antenna;

(10.5) determining which one of the antennas has the shortest distance to a selected pixel, said antenna being a serving antenna of said selected pixel;

(10.6) constituting a pixel coverage of said serving antenna by selecting all of said pixels having a shortest distance to said serving antenna;

(10.7) constructing a rectangular area covering said pixel coverage; and

(10.8) constructing a circle having a center being the intersecting point of the diagonal lines of said rectangular area and a radius of one-half of said diagonal line.

11. An enhanced cell coverage system for utilization in a cellular mobile communication system having a plurality of coverage cells, a plurality of antennas, a plurality of mobile terminals, and a timing advance (TA) cell coverage device for determining a cell coverage by a TA method, said enhanced cell coverage system comprising:

an enhanced cell coverage device determining a location having an enhanced resolution in the cellular mobile communication system; and

a selector, coupled to the timing advance cell coverage device and to said enhanced cell coverage device, for selecting between the cell coverage generated by the timing advance cell coverage device and an enhanced cell coverage generated by said enhanced cell coverage device, said selection being responsive to the greater of the TA resolution and said enhanced resolution.

12. The enhanced cell coverage system of claim 11 wherein said enhanced cell coverage device comprises:

coverage distribution means for distributing the sections responsive to the shortest distance of a cell to an antenna; and

enhanced cell coverage generating means, coupled to said coverage distribution means, for generating a plurality of enhanced cell coverages of the antennas responsive to said coverage distribution.

13. The device of claim 12, wherein said coverage distribution means comprises:

classifying means for classifying each of the antenna coverages as outdoor macro cells, outdoor micro cells and indoor micro cells, said classification responsive to the covering range, antenna directivity and traffic of said antenna;

pixel dividing means, coupled to said classifying means, for dividing said communication system coverage of the mobile system into a plurality of pixels; and

pixel mapper means, coupled to said pixel dividing means, for constructing a pixel map including all of the locations of said plurality of pixels.

14. The device of claim 13, wherein said enhanced cell coverage generating means comprises:

distance calculation means, coupled to said pixel mapper means, for determining the distances between each of said plurality of pixels and its nearest one of the plurality antennas;

proximate antenna calculating means, coupled to said distance calculation means, for determining which one of the antennas has the shortest distance to a selected pixel, said antenna being a serving antenna of said selected pixel;

pixel coverage means, coupled to said proximate antenna calculating means, for constituting a pixel coverage of said serving antenna by selecting all of said pixels having a shortest distance to said serving antenna;

area coverage constructing means, coupled to said pixel coverage means, for constructing a rectangular area covering said pixel coverage; and

circle constructing means, coupled to said area coverage constructing means, for determining said enhanced cell coverage by defining a circle having a center being the intersecting point of the diagonal lines of said rectangular area and a radius of one-half of said diagonal line for determining an enhanced cell coverage.

15. The enhanced cell coverage system of claim 11, wherein the cellular mobile communication system utilizes time-division multiple access.

16. The device claim 15, wherein the time-division multiple access mobile communication system is a digital GSM system.

17. The enhanced cell coverage system of claim 11 further comprising an information transceiver system, including an information database, for receiving location information from the plurality of mobile terminals, and for transmitting enhanced cell coverage information from said enhanced cell coverage device to the plurality of mobile terminals for locating a mobile terminal.