Mobile communication control method and system and mobile station thereof

• US 7,031,712 B2
• Filed: 11/21/2001
• Issued: 04/18/2006
• Est. Priority Date: 11/22/2000
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Hamabe, Kojiro, Takano, Nahoko
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): Pham, Tuan
• Application Number:
  US09/989,662
• Publication Number:
  US 20020061731A1
• Time in Patent Office: 1,609 Days
• Field of Search: 455/436, 455/437, 455/439, 455/442, 455/443, 455/525, 455/67.11, 455/69, 455/522, 455/524, 455/561
• US Class Current: 455/442
• CPC Class Codes: H04B 7/022 Site diversity; Macro-diversity using two or more spaced independent antennas H04B7/04
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff

Abstract

In case of making site selection diversity transmit power control, all handover base stations are enabled for transmission depending on a state of the transmission power value of a dedicated data signal from the base stations, thereby preventing a trafic capacity from decreasing due to an increase in the transmission power of a dedicated control signal at a non-transmitting base station, or a received signal quality from degrading at a mobile station because the transmission power value of the transmitting base station reaches a maximum transmission power of base station. A mobile station measures a common pilot signal and a dedicated control signal transmitted from each handover base station by means of a receiving monitor, estimates the transmission power value of the dedicated control signal at each handover base station from a difference thereof, and estimates a difference in the transmission power value of the dedicated control signal between the handover base stations. In the case where this difference is greater than or equal to a predetermined threshold value, a transmitting base station designating section designates all of the handover base stations to be enabled for transmission.

Claims

1. A mobile communication control method in which a mobile station transmits data using at least one currently transmitting base station and also sets a link with base stations forming an active set of base stations, comprising:

measuring a received signal quality of a pilot signal transmitted from each of said active set of base stations;

determining at least one transmitting base station from among the active set of base stations in accordance with the measured results, said determining further comprises enabling for transmission all of the active set base stations depending on a state of transmission power value from said at least one currently transmitting base station;

transmitting a dedicated control signal to said mobile station from said active set of base stations;

transmitting a dedicated data signal to said mobile station from said at least one currently transmitting base station;

estimating a transmission power value of the dedicated control signal transmitted by said active set of base stations, and

making each of the active set of base stations a transmitting base station when an estimated value of the transmission power value of the dedicated control signal transmitted by the active set of base stations other than said at least one currently transmitting base station is greater than or equal to a predetermined threshold value for the estimated value of transmission power value of the dedicated control signal transmitted by said at least one currently transmitting base station.

2. The mobile communication control method according to claim 1, further comprising a step of measuring the received powers of a common pilot signal that said active set base station transmits at a predetermined power value and said dedicated control signal or said dedicated data signal transmitted at a power value under the transmission power control in said mobile station, and estimating a power value of said dedicated control signal or said dedicated data signal from a difference between the received power of said common pilot signal and the received power of said dedicated control signal or said dedicated data signal.

3. The mobile communication control method according to claim 1, wherein each of the active set of base stations transmits a dedicated control signal to the mobile station and wherein only each of said at least one transmitting base station transmits dedicated data signal to the mobile station.

4. The mobile communication control method according to claim 1, further comprising notifying the active set of base stations of the determined at least one transmitting base station.

5. A mobile communication control method in which a mobile station transmits data using at least one currently transmitting base station and also sets a link with base stations forming an active set of base stations, comprising:

measuring a received signal quality of a pilot signal transmitted from each of said active set of base stations;

determining at least one transmitting base station from among the active set of base stations in accordance with the measured results, said determining further comprises enabling for transmission all of the active set base stations depending on a state of transmission power value from said at least one currently transmitting base station;

transmitting a dedicated data signal to said mobile station from said at least one currently transmitting base station;

estimating a transmission power value of the dedicated data signal transmitted by said at least one currently transmitting base station, and

making each of the active set of base stations a transmitting base station when a difference between an estimated value of the transmission power value of said at least one currently transmitting base station and a predetermined maximum transmission power value of base station is smaller than or equal to a predetermined threshold value.

6. A mobile communication method in which a mobile station transmits data using at least one currently transmitting base station and also sets a link with base stations forming an active set of base stations, comprising:

measuring a received signal quality of a pilot signal transmitted from each of said active set of base stations;

determining at least one transmitting base station from among the active set of base stations in accordance with the measured results, said determining further comprises enabling for transmission all of the active set base stations depending on a state of transmission power value from said at least one currently transmitting base station;

measuring the received signal quality of the dedicated data signal transmitted from said at least one currently transmitting base station in said mobile station, and making all of the active set base stations a transmitting base station when the received signal quality is less than a predetermined signal quality even if said at least one currently transmitting base station makes the transmission at the predetermined maximum transmission power value.

7. A mobile communication system comprising:

a mobile station;

at least one currently transmitting base station transmitting data to and from the mobile station; and

base stations with which the mobile station sets a link, forming an active set of base stations,

wherein the mobile station measures a received signal quality of a pilot signal transmitted from each of said base stations, determines at least one transmitting base station from the active set of base stations in accordance with the measured results,

wherein the determining of the at least one transmitting base comprises enabled for transmission all of the active set of base stations depending on a state of transmission power value from said at least one currently transmitting base station,

wherein said active set of base stations transmits a dedicated control signal to said mobile station, said at least one currently transmitting base station transmits a dedicated data signal and the dedicated control signal, and said mobile station estimates a transmission power value of the dedicated control signal transmitted by said active set of base stations, and

wherein each base station from the active set of base stations are enabled for transmission when an estimated value of the transmission power value of the dedicated control signal transmitted by the active set of base stations other than said at least one currently transmitting base station is greater than or equal to a predetermined threshold value for the estimated value of transmission power value of the dedicated control signal transmitted by said at least one currently transmitting base station.

8. The mobile communication system according to claim 7,

wherein said mobile station measures the received powers of a common pilot signal that said active set base station transmits at a predetermined power value and said dedicated control signal or said dedicated data signal transmitted at a power value under the transmission power control, and estimates a power value of said dedicated control signal or said dedicated data signal from a difference between the received power of said common pilot signal and the received power of said dedicated control signal or said dedicated data signal.

9. The mobile communication system according to claim 7, wherein said mobile station notifies the determined result to said active set base stations.

10. A mobile communication system comprising:

a mobile station;

at least one currently transmitting base station transmitting data to and from the mobile station; and

base stations with which the mobile station sets a link, forming an active set of base stations,

wherein the mobile station measures a received signal quality of a pilot signal transmitted from each of said base stations, determines at least one transmitting base station from the active set of base stations in accordance with the measured results,

wherein the determining of the at least one transmitting base comprises enabled for transmission all of the active set of base stations depending on a state of transmission power value from said at least one currently transmitting base station,

wherein said at least one currently transmitting base station transmits a dedicated data signal to said mobile station, and said mobile station estimates a transmission power value of the dedicated data signal transmitted by said at least one currently transmitting base station, and

wherein each base station of the active set of base stations is enabled for transmission, if a difference between an estimated value of the transmission power value of said at least one currently transmitting base station and a predetermined maximum transmission power value of base station is smaller than or equal to a predetermined threshold value.

11. A mobile communication system comprising:

a mobile station;

at least one currently transmitting base station transmitting data to and from the mobile station; and

base stations with which the mobile station sets a link, forming an active set of base stations,

wherein the mobile station measures a received signal quality of a pilot signal transmitted from each of said base stations, determines at least one transmitting base station from the active set of base stations in accordance with the measured results,

wherein the determining of the at least one transmitting base comprises enabled for transmission all of the active set of base stations depending on a state of transmission power value from said at least one currently transmitting base station,

wherein said mobile station measures the received signal quality of a signal transmitted from said at least one currently transmitting base station, and

all of the active set of base stations are enabled for transmission when the received signal quality is less than a predetermined signal quality even if said at least one currently transmitting base station makes the transmission at a predetermined maximum transmission power value.

12. A mobile station which transmits data using at least one currently transmitting base station and which sets a link with base stations forming an active set of base stations, comprising:

means for measuring received signal quality of a pilot signal transmitted from said base stations; and

means for determining at least one transmitting base station from the active set of base stations in accordance with the measured results,

wherein said determining at least one transmitting base station further comprises enabling for transmission each base station from the active set of base stations depending on a state of transmission power value of said at least one currently transmitting base station, and

wherein said mobile station estimates a transmission power value of the dedicated control signal transmitted by said active set of base stations, and notifies that all base stations of the active set of base stations are enabled for transmission when an estimated value of the transmission power value of said dedicated control signal transmitted by the active set of base stations other than said at least one currently transmitting base station is greater than or equal to a predetermined threshold value for the estimated value of transmission power value of the dedicated control signal transmitted by said at least one currently transmitting base station.

13. The mobile station according to claim 12,

wherein said mobile station measures the received powers of a common pilot signal that said active set base station transmits at a predetermined power value and said dedicated control signal or said dedicated data signal transmitted at a power value under the transmission power control, and estimates a power value of said dedicated control signal or said dedicated data signal from a difference between the received power of said pilot signal and the received power of said dedicated control signal or said dedicated data signal.

14. The mobile station according to claim 12, further comprising means for notifying the determined result to said active set of base stations.

15. A mobile station which transmits data using at least one currently transmitting base station and which sets a link with base stations forming an active set of base stations, comprising:

means for measuring received signal quality of a pilot signal transmitted from said base stations; and

means for determining at least one transmitting base station from the active set of base stations in accordance with the measured results,

wherein said determining at least one transmitting base station further comprises enabling for transmission each base station from the active set of base stations depending on a state of transmission power value of said at least one currently transmitting base station, and

wherein said mobile stations estimates a transmission power value of the dedicated data signal transmitted by said at least one currently transmitting base station, and notifies that each base station from the active set of base stations are enabled for transmission when a difference between an estimated value of the transmission power value of said at least one currently transmitting base station and predetermined maximum transmission power value of base station is smaller than or equal to a predetermined threshold value.

16. A mobile station which transmits data using at least one currently transmitting base station and which sets a link with base stations forming an active set of base stations, comprising:

means for measuring received signal quality of a pilot signal transmitted from said base stations; and

means for determining at least one transmitting base station from the active set of base stations in accordance with the measured results,

wherein said determining at least one transmitting base station further comprises enabling for transmission each base station from the active set of base stations depending on a state of transmission power value of said at least one currently transmitting base station, and

wherein said mobile station measures the received signal quality of a signal transmitted from said at least one currently transmitting base station, and notifies that all of the active set base stations are enabled for transmission when the received signal quality is less than a predetermined signal quality even if said at least one currently transmitting base station makes the transmission at predetermined maximum transmission power value.