RADIO COMMUNICATION SYSTEM, BASE STATION APPARATUS AND USER TERMINAL

• US 20130039302A1
• Filed: 02/15/2011
• Published: 02/14/2013
• Est. Priority Date: 02/15/2010
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Miki, Nobuhiko, Umesh, Anil, Okubo, Naoto
• Granted Patent: US 8,982,817 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04W 28/04 Error control

Abstract

The present invention maintains communication even during a transition period in which ON/OFF of the CIF is switched by higher layer signaling or during a transition period in which the number of component carrier aggregations is increased/decreased. In a radio communication system in which an LTE-A system, in which an LTE-A system to add or remove the frequency band to assign for communication between a base station apparatus (20) and a mobile terminal apparatus (10) on a per component carrier basis, and an LTE system to perform communication between the base station apparatus (20) and the mobile terminal apparatus (10) using one fixed fundamental frequency block, are arranged in an overlapping manner, in the LTE-A system, one of the fundamental frequency blocks assigned to the mobile terminal apparatus (10) is determined as an anchor block, and the anchor block supports the same operation as in the LTE system.

Claims

1. A radio communication system in which a first communication system and a second communication system are arranged in an overlapping manner, the first communication system adding or removing a frequency band to assign for communication between a base station apparatus and a user terminal on a per fundamental frequency block basis, and the second communication system performing communication between the base station apparatus and the user terminal via one fixed fundamental frequency block,

wherein, in the first communication system, one of fundamental frequency blocks assigned to the user terminal is determined as an anchor block, and the anchor block supports a same operation as in the second communication system.

2. The radio communication system as defined in claim 1, wherein:

in the first communication system, resources are allocated such that a shared data channel for transmission of user data, and downlink control information for demodulation of the shared data channel, are mapped to the same or different fundamental frequency blocks, and whether or not to add a carrier indicator of a fundamental frequency block to which the shared data channel is mapped, to the downlink control information, is controlled; and

in the anchor block, downlink control information, which is for demodulating the shared data channel mapped to the anchor block and to which the carrier indicator is not added, is mapped in a control channel region of the anchor block.

3. The radio communication system as defined in claim 1, wherein, in the first communication system, when the carrier indicator is added to the downlink control information to be mapped in a control channel region of each fundamental frequency block assigned to the user terminal, downlink control information in which the carrier indicator is added and downlink control information in which the carrier indicator is not added are mapped to the anchor block.

4. A base station apparatus in a radio communication system in which a first communication system and a second communication system are arranged in an overlapping manner, the first communication system adding or removing a frequency band to assign for communication between a base station apparatus and a user terminal on a per fundamental frequency block basis, and the second communication system performing communication between the base station apparatus and the user terminal via one fixed fundamental frequency block,

wherein, in the first communication system, one of fundamental frequency blocks assigned to the user terminal is determined as an anchor block, and the anchor block supports a same operation as in the second communication system.

5. The base station apparatus as defined in claim 4, comprising:

a section that allocates resources such that a shared data channel for transmission of user data, and downlink control information for demodulation of the shared data channel, are mapped to the same or different fundamental frequency blocks;

a section that controls whether or not to add a carrier indicator of a fundamental frequency block to which the shared data channel is mapped, to the downlink control information; and

a section that, in the anchor block, regardless of whether or not the carrier indicator exists, maps downlink control information, which is for demodulating the shared data channel mapped to the anchor block and to which the carrier indicator is not added, in a control channel region of the anchor block.

6. A user terminal in a radio communication system in which a first communication system and a second communication system are arranged in an overlapping manner, the first communication system adding or removing a frequency band to assign for communication between a base station apparatus and a user terminal on a per fundamental frequency block basis, and the second communication system performing communication between the base station apparatus and the user terminal via one fixed fundamental frequency block,

wherein one of fundamental frequency blocks assigned by the base station apparatus is determined as an anchor block that supports a same operation as in the second communication system, and, in this anchor block, downlink reception processing is performed in accordance with the second communication system.

7. A radio communication system in which a first communication system and a second communication system are arranged in an overlapping manner, the first communication system adding or removing a frequency band to assign for communication between a base station apparatus and a user terminal on a per fundamental frequency block basis, and the second communication system performing communication between the base station apparatus and the user terminal via one fixed fundamental frequency block, wherein:

in the first and second communication systems, a common search space that is common between user terminals and a user specific search space that is separate between user terminals are assigned to a downlink control channel region of the fundamental frequency block; and

the base station apparatus;

maps user common control information, which a plurality of user terminals connecting to a same cell, need to receive, to the common search space;

maps user-specific control information, which each user terminal needs to receive individually, to the user-specific search space, in a configuration according to the first communication system; and

furthermore, maps the user-specific control information, which each user terminal needs to receive individually, to the common search space, fixedly to the configuration which guarantees the same operation as in the second communication system.

8. The radio communication system as defined in claim 7, wherein, as a user-specific control information configuration for the first communication system, the base station apparatus includes a carrier indicator of a fundamental frequency block, to which a shared data channel to be demodulated using the user-specific control information is mapped.