BASE STATION, TERMINAL, AND COMMUNICATION SYSTEM

• US 20160014746A1
• Filed: 09/23/2015
• Published: 01/14/2016
• Est. Priority Date: 03/29/2013
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Ode, Takayoshi
• Granted Patent: US 10,057,894 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 5/00 Arrangements affording multiple use of the transmission path
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0032 Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0085 when channel conditions change
• 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
• CPC Class Codes: H04W 72/51 based on terminal or device properties

Abstract

A communication system includes: a first base station; one or more second base stations; and a terminal. The first base station includes an acquiring unit that acquires information about reception time, at which the terminal receives information sent from the first base station and the one or more second base stations by using one or more frequency bands or transmission time of each frequency band at the terminal or both, and a first control unit that controls, based on information about the reception time or the transmission time acquired by the acquiring unit, frequency bands that are simultaneously used by the terminal. The terminal includes a second control unit that performs control, in accordance with the control performed by the first base station, such that communication is performed by simultaneously using the frequency bands.

Claims

1. A communication system comprising:

a first base station;

one or more second base stations; and

a terminal, wherein

the first base station includes

an acquiring unit that acquires information about reception time, at which the terminal receives information sent from the first base station and the one or more second base stations by using one or more frequency bands or transmission time of each frequency band at the terminal or both, and

a first control unit that controls, based on information about the reception time or the transmission time acquired by the acquiring unit, frequency bands that are simultaneously used by the terminal, and

the terminal includes

a second control unit that performs control, in accordance with the control performed by the first base station, such that communication is performed by simultaneously using the frequency bands.

2. The communication system according to claim 1, wherein

the acquiring unit acquires information about one or more first reception time differences, as information about the reception time, based on first reception time of information sent from the first base station by using a first frequency band and second reception time of information sent from the first base station and the one or more second base stations by using one or more second frequency bands,

the first control unit creates, based on the information about the one or more first reception time differences, control information about a second frequency band that is simultaneously used with the first frequency band by the terminal, and

the first base station further includes a transmitting unit that notifies the terminal of the control information.

3. The communication system according to claim 2, wherein the first control unit includes a selecting unit that selects, from among the one or more second frequency bands based on the information about the one or more first reception time differences, the second frequency band that is simultaneously used with the first frequency band by the terminal and creates control information about the selected second frequency band.

4. The communication system according to claim 3, wherein the selecting unit selects, from among the one or more second frequency bands, by using the first reception time differences and a first threshold that is previously determined in the first base station or determined between the first base station and the terminal, the second frequency band simultaneously used with the first frequency band by the terminal.

5. The communication system according to claim 4, wherein the selecting unit controls the first threshold in accordance with a protection period between a downlink transmission period and an uplink reception period.

6. The communication system according to claim 4, wherein, when the selecting unit is not able to select, from among the one or more second frequency bands, the second frequency band that is simultaneously used with the first frequency band by the terminal, the selecting unit selects, from among one or more third frequency bands that are different from the first frequency band by a frequency equal to or greater than a predetermined frequency, a third frequency band that is simultaneously used with the first frequency band by the terminal.

7. The communication system according to claim 6, wherein

the acquiring unit further acquires information that indicates one or more second reception time differences between the first frequency band and each of the third frequency bands, and

the selecting unit selects, from among the one or more third frequency bands, by using the second reception time differences and a second threshold that is previously determined in the first base station or determined between the first base station and the terminal, the third frequency band simultaneously used with the first frequency band by the terminal.

8. A base station that performs communication with a terminal that performs communication with one or more base stations by simultaneously using a plurality of frequency bands, the base station comprising:

an acquiring unit that acquires at least one of information about reception time, at which the terminal receives information sent from the base station and one or more base stations other than the base station by using one or more frequency bands, and transmission time of each frequency band at the terminal; and

a control unit that controls, based on information about the reception time or the transmission time acquired by the acquiring unit, frequency bands that are simultaneously used by the terminal.

9. A terminal that performs communication with one or more base stations by simultaneously using a plurality of frequency bands, the terminal comprising:

a reception time measuring unit that measures reception time of information sent from a first base station by using a first frequency band and that measures reception time of information sent from each of the first base station and a second base station by using a second frequency band;

a transmitting unit that notifies the first base station of at least one of reception time information and information about a candidate for the second frequency band that is simultaneously used with the first frequency band, based on reception time measurement results in the reception time measuring unit;

a receiving unit that receives control information about a second frequency band that is selected based on the reception time information or the information about the candidate for the second frequency band and that is simultaneously used with the first frequency band; and

a control unit that performs control, based on the control information, such that communication is performed by simultaneously using the first frequency band and the second frequency band.

10. A terminal that performs communication with one or more base stations by simultaneously using a plurality of frequency bands, the terminal comprising:

a receiving unit that receives first transmission time information sent from a first base station by using a first frequency band and that receives second transmission time information sent from each of the first base station and a second base station by using a second frequency band; and

a transmitting unit that notifies the first base station of at least one of the second transmission time information and information about a candidate for the second frequency band that is selected based on the first transmission time information and the second transmission time information and that is simultaneously used with the first frequency band.