USER TERMINAL, RADIO BASE STATION, RADIO COMMUNICATION SYSTEM AND RADIO COMMUNICATION METHOD

• US 20150282174A1
• Filed: 09/10/2013
• Published: 10/01/2015
• Est. Priority Date: 10/09/2012
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Takeda, Kazuaki, Nagata, Satoshi, Kishiyama, Yoshihisa, Ishii, Hiroyuki
• Granted Patent: US 9,674,838 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 5/1469 using time-sharing
• CPC Class Codes: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/1268 of uplink data flows
• CPC Class Codes: H04W 72/27 between access points
• CPC Class Codes: H04W 76/15 Setup of multiple wireless link connections
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

The present invention is designed to enable 1-CC transmission when carrier aggregation is carried out by aggregating a first component carrier, which is used in a macro cell, and a second component carrier, which is used in a small cell. A user terminal according to the present invention receives duration configuration information, which indicates a first duration to communicate with a macro base station by using the first component carrier, and a second duration to communicate with a small base station by using the second component carrier, configures the first duration and the second duration based on the duration configuration information, transmits uplink signals for the macro base station by using the first component carrier in the first duration, and transmits uplink signals for the small base station by using the second component carrier in the second duration.

Claims

1. A user terminal in a radio communication system where carrier aggregation is carried out by aggregating a first component carrier, which is used in a macro cell, and a second component carrier, which is used in a small cell, the user terminal comprising:

a receiving section that receives duration configuration information, which indicates a first duration to communicate with a macro base station forming the macro cell by using the first component carrier, and a second duration to communicate with a small base station forming the small cell by using the second component carrier;

a configuration section that configures the first duration and the second duration based on the duration configuration information; and

a transmitting section that, in the first duration, transmits an uplink signal for the macro base station by using the first component carrier, and that, in the second duration, transmits an uplink signal for the small base station by using the second component carrier.

2. The user terminal according to claim 1, wherein the receiving section receives, in the first duration, a downlink signal from the macro base station by using the first component carrier, and receives, in the second duration, a downlink signal from the small base station by using the second component carrier.

3. The user terminal according to claim 1, wherein:

the receiving section receives duration change information for changing the lengths of the first duration and the second duration; and

the configuration section changes the lengths of the first duration and the second duration based on the duration change information.

4. The user terminal according to claim 1, wherein, when one of the first component carrier and the second component carrier employs a time division duplexing (TDD) scheme and the other one employs a frequency division duplexing (FDD) scheme, the transmitting section transmits the uplink signals by using the component carrier where the FDD scheme is employed, in a downlink subframe of the component carrier where the TDD scheme is employed.

5. The user terminal according to claim 1, wherein, when the first component carrier and the second component carrier both employ a time division duplexing (TDD) scheme:

the receiving section receives shift information for shifting uplink subframes of the first component carrier and/or the second component carrier; and

the transmitting section transmits the uplink signals in the uplink subframe that are configured based on the shift information.

6. The user terminal according to claim 1, wherein, when carrier aggregation is carried out by aggregating three or more component carriers including the first component carrier and the second component carrier, the configuration section configures separate durations on a per component carrier basis.

7. The user terminal according to claim 1, wherein, when carrier aggregation is carried out by aggregating three or more component carriers including the first component carrier and the second component carrier, the configuration section configures a common duration that is shared between a plurality of component carriers.

8. A radio base station that forms a macro cell in a radio communication system where carrier aggregation is carried out by aggregating a first component carrier, which is used in the macro cell, and a second component carrier, which is used in a small cell, the radio base station comprising:

a transmitting section that transmits duration configuration information to a user terminal, the duration configuration information indicating a first duration to communicate with the radio base station by using the first component carrier, and a second duration to communicate with the small base station forming the small cell by using the second component carrier; and

a receiving section that receives from the user terminal by using the first component carrier in the first duration.

9. A radio communication system where carrier aggregation is carried out by aggregating a first component carrier, which is used in a macro cell, and a second component carrier, which is used in a small cell, wherein:

a macro base station forming the macro cell comprises a transmitting section that transmits duration configuration information to a user terminal, the duration configuration information indicating a first duration to communicate with the macro base station by using the first component carrier, and a second duration to communicate with a small base station forming the small cell by using the second component carrier; and

the user terminal comprises;

a configuration section that configures the first duration and the second duration based on the duration configuration information; and

a transmitting section that, in the first duration, transmits an uplink signal for the macro base station by using the first component carrier, and that, in the second duration, transmits an uplink signal for the small base station by using the second component carrier.

10. A radio communication method to carry out carrier aggregation by aggregating a first component carrier, which is used in a macro cell, and a second component carrier, which is used in a small cell, the radio communication method comprising the steps in which:

a macro base station forming the macro cell transmits duration configuration information to a user terminal, the duration configuration information indicating a first duration to communicate with the macro base station by using the first component carrier, and a second duration to communicate with a small base station forming the small cell by using the second component carrier; and

the user terminal;

configures the first duration and the second duration based on the duration configuration information; and

in the first duration, transmits an uplink signal for the macro base station by using the first component carrier, and, in the second duration, transmits an uplink signal for the small base station by using the second component carrier.