BASE STATION, TERMINAL DEVICE, CONTROL CHANNEL ASSIGNMENT METHOD AND REGION SIZE DETERMINATION METHOD

• US 20110199995A1
• Filed: 04/25/2011
• Published: 08/18/2011
• Est. Priority Date: 10/30/2008
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: ITO, Akira, DATEKI, Takashi
• Granted Patent: US 8,824,388 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 5/00 Arrangements affording multiple use of the transmission path
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

In a base station that performs radio data communication with terminal devices by using a plurality of bands of which each has a data channel region to which a data channel is assigned and a control channel region to which a control channel is assigned, the base station includes a control channel assigning unit that assigns a control channel for the terminal device at a location corresponding to a band to which a data channel assigned to the terminal device belongs, in the control channel region of any band of the plurality of bands, and a control channel transmitting unit that transmits the control channel to the terminal device at the location assigned by the control channel assigning unit.

Claims

1. A base station that performs radio data communication with terminal devices by using a plurality of bands of which each has a data channel region to which a data channel is assigned and a control channel region to which a control channel is assigned, the base station comprising:

a control channel assigning unit that assigns a control channel for the terminal device at a location corresponding to a band to which a data channel assigned to the terminal device belongs, in the control channel region of any band of the plurality of bands; and

a control channel transmitting unit that transmits the control channel to the terminal device at the location assigned by the control channel assigning unit.

2. The base station according to claim 1, wherein the control channel assigning unit assigns the control channel for the terminal device to the control channel region in any one of the plurality of bands in such a manner that a detection sequence of the control channels performed by the terminal device is identical to a sequence of frequency bands of the bands corresponding to the control channels.

3. The base station according to claim 2, wherein the control channel assigning unit sets the sequence of frequency bands of the bands corresponding to the control channels as an ascending order or a descending order of the frequency bands of the bands by using the band to which the control channel for the terminal device is assigned as a starting point.

4. The base station according to claim 3, wherein the control channel assigning unit sets a control channel detected by the terminal device next to the control channel corresponding to a band having the highest/lowest frequency band to a control channel corresponding to a band having the lowest/highest frequency band, as the detection sequence of the control channels performed by the terminal device.

5. The base station according to claim 1, further comprising a carrier determining unit that determines, among the plurality of bands, bands to which the data channel for each of the terminal devices is assigned in an ascending order or a descending order of frequency bands of the bands by using the band to which the control channel for the terminal device is assigned as a starting point.

6. The base station according to claim 5, wherein the carrier determining unit modifies a band to which the data channel is assigned in accordance with a communication situation of each of the bands to which the data channel is assigned.

7. The base station according to claim 2, wherein the control channel assigning unit assigns the control channels corresponding to the data channels at consecutive locations in the control channel region of the band to which the control channel for the terminal device is assigned.

8. The base station according to claim 1, wherein a control channel other than the control channel assigned at a location first detected by the terminal device, in the control channel region of the band to which the control channel for the terminal device is assigned, includes only information that indicates an assignment location of the data channel.

9. A terminal device that performs radio data communication with a base station by using a plurality of bands of which each has a data channel region to which a data channel is assigned and a control channel region to which a control channel is assigned, the terminal device comprising:

a control channel receiving unit that receives, from the base station, a control channel assigned to a control channel region of a band to which a control channel for the terminal device is assigned; and

a data channel receiving unit that receives a data channel at an assignment location indicated by the control channel in a data channel region of a band corresponding to a location to which the control channel received by the control channel receiving unit is assigned in the control channel region.

10. The terminal device according to claim 9, further comprising:

a storage unit that stores therein a band to which the control channel for the device itself is assigned among the plurality of bands and a correspondence relationship between the band and an assignment location of the control channel in the control channel region of the band; and

an information updating unit that modifies, in accordance with a request of the base station, the correspondence relationship between the band and the assignment location of the control channel in the control channel region of the band stored in the storage unit to which the control channel for the device itself is assigned.

11. The terminal device according to claim 9, wherein the control channel receiving unit determines, upon receiving the control channel, that another control channel is assigned at an assignment location continued next to the assignment location of the control channel and receives the control channel at the continued assignment location.

12. A method for assigning a control channel to a control channel region by using a plurality of bands of which each has a data channel region to which a data channel is assigned and a control channel region to which a control channel is assigned when radio data communication is performed between a base station and a terminal device, the method comprising

assigning, by the base station, a control channel for the terminal device at a location corresponding to a band to which a data channel assigned to the terminal device belongs, in the control channel region of any band of the plurality of bands.