METHOD FOR CONTROLLING HANDOVER, USER EQUIPMENT, BASE STATION, AND RADIO COMMUNICATION SYSTEM

• US 20120314606A1
• Filed: 01/21/2011
• Published: 12/13/2012
• Est. Priority Date: 02/25/2010
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Takano, Hiroaki
• Granted Patent: US 9,351,204 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04L 1/0046 Code rate detection or code type detection H04L1/0038 takes precedence; detection of the data rate H04L25/0262; for packet format H04L1/0091
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04W 36/0072 of resource information of target access point
• CPC Class Codes: H04W 36/0085 Hand-off measurements
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

Provided is a method for controlling a handover from a first base station to a second base station by a user equipment that performs radio communication over a communication channel formed by aggregating a plurality of component carriers, wherein scheduling information on each component carrier is transmitted to the user equipment according to either of a straight scheduling method and a cross scheduling method, and the method includes at the first base station, commanding first the user equipment to perform a handover from the first base station to the second base station on a second component carrier to be operated according to the straight scheduling method in the second base station, when it is determined that a handover on a first component carrier following the cross scheduling method is to be executed.

Claims

1. A method for controlling a handover from a first base station to a second base station by a user equipment that performs radio communication over a communication channel formed by aggregating a plurality of component carriers,

wherein scheduling information on each component carrier is transmitted to the user equipment according to either of a straight scheduling method and a cross scheduling method, and

the method includes

at the first base station, commanding first the user equipment to perform a handover from the first base station to the second base station on a second component carrier to be operated according to the straight scheduling method in the second base station, when it is determined that a handover on a first component carrier following the cross scheduling method is to be executed.

2. The method according to claim 1, wherein the first base station commands the user equipment to perform a handover on the second component carrier in which a channel for transmitting scheduling information on the first component carrier is positioned before a handover on the first component carrier.

3. The method according to claim 2, further comprising:

at the first base station, commanding the user equipment to perform a handover on the first component carrier.

4. The method according to claim 1, wherein the first component carrier and the second component carrier are the same component carrier, and

the method further includes, at the first base station, changing a scheduling information transmission method on the first component carrier from the cross scheduling method to the straight scheduling method before a first handover is executed.

5. The method according to claim 4, wherein the first base station changes the scheduling information transmission method on the first component carrier from the cross scheduling method to the straight scheduling method according to a change request of the scheduling information transmission method from the user equipment that has executed measurement.

6. The method according to claim 4, wherein the first base station changes the scheduling information transmission method on the first component carrier from the cross scheduling method to the straight scheduling method after a handover request is confirmed by the second base station.

7. The method according to claim 1, wherein the first component carrier and the second component carrier are the same component carrier, and

the second component carrier is operated according to the straight scheduling method in the second base station after a handover from the first base station to the second base station is performed.

8. A user equipment, comprising:

a radio communication unit that performs radio communication with a base station over a communication channel formed by aggregating a plurality of component carriers;

a control unit that controls a handover from a first base station to a second base station by the radio communication unit; and

a quality measuring unit that measures a channel quality of the communication channel between the user equipment and the first base station,

wherein scheduling information on each component carrier is transmitted according to either of a straight scheduling method and a cross scheduling method, and

when it is determined that a handover on a first component carrier following the cross scheduling method is to be executed, a handover from the first base station to the second base station on a second component carrier to be operated according to the straight scheduling method in the second base station is first executed according to a command from the first base station.

9. A base station, comprising:

a radio communication unit that performs radio communication with a user equipment over a communication channel formed by aggregating a plurality of component carriers; and

a control unit that controls a handover to another base station by the user equipment,

wherein scheduling information on each component carrier is transmitted according to either of a straight scheduling method and a cross scheduling method, and

when it is determined that a handover on a first component carrier following the cross scheduling method is to be executed, the control unit commands first the user equipment to perform a handover to the other base station on a second component carrier to be operated according to the straight scheduling method in the other base station.

10. A radio communication system, comprising:

a user equipment that performs radio communication over a communication channel formed by aggregating a plurality of component carriers;

a first base station that provides the user equipment with a service over the communication channel; and

a second base station that is a target of a handover from the first base station by the user equipment,

wherein scheduling information on each component carrier is transmitted according to either of a straight scheduling method and a cross scheduling method, and

when it is determined that a handover on a first component carrier following the cross scheduling method is to be executed, the first base station commands first the user equipment to perform a handover on a second component carrier to be operated according to the straight scheduling method in the second base station.