Terminal, base station, and communication method which set a transmission power of an uplink signal

• US 9,832,732 B2
• Filed: 11/07/2012
• Issued: 11/28/2017
• Est. Priority Date: 11/07/2011
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Ouchi, Wataru, Imamura, Kimihiko, Nakashima, Daiichiro
• Primary Examiner(s): Pan, Yuwen
• Assistant Examiner(s): Chen, Zhitong
• Application Number:
  US14/356,614
• Publication Number:
  US 20140295909A1
• Time in Patent Office: 1,847 Days
• CPC Class Codes: H04B 7/005 Control of transmission; Equalising
• CPC Class Codes: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• CPC Class Codes: H04B 7/216 Code division or spread-spectrum multiple access [CDMA, SSMA]
• CPC Class Codes: H04W 52/04 TPC
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 52/245 taking into account received signal strength
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

In a communication system in which a base station and a terminal communicates, the base station and the terminal communicates efficiently. There is provided the terminal which communicates with the base station, the terminal including: a reception unit 605 which detects a transmission power control (TPC) command in a downlink control information (DCI) format and obtains a power correction value from the TPC command; and a transmission power control unit 6015 which sets transmission power of an uplink signal based on a power correction value obtained from a first TPC command when the terminal is in a first state and sets transmission power of the uplink signal based on a power correction value obtained from a second TPC command when the terminal is in a second state.

Claims

1. A terminal comprising:

reception circuitry that;

receives a higher layer signal including a parameter to be used for uplink power control, the parameter indicating whether a subframe belongs to a first subframe set or a second subframe set, and the first subframe set being different from the second subframe set; and

detects a transmission power control (TPC) command in a downlink control information (DCI) format, and obtains a power correction value from the TPC command, the TPC command including a first power correction value in a case that the subframe belongs to the first subframe set, the TPC command including a second power correction value in a case that the subframe belongs to the second subframe set, and the first power correction value being different from the second power correction value; and

transmission power control circuitry that sets a transmission power of an uplink signal to be transmitted in the subframe, based on the first power correction value or the second power correction value, which is included in the TPC command detected.

2. The terminal according to claim 1, wherein

the terminal communicates with a first base station and a second base station, and

the first subframe set and the second subframe set are configured respectively for the first base station and the second base station.

3. The terminal according to claim 2, wherein

the transmission power control circuitry:

sets the transmission power of the uplink signal based on a single power control in a case that the terminal is in a first state,

sets the transmission power of the uplink signal based on one or more power controls in a case that the terminal is in a second state, and

the first state and the second state are associated with a configuration of the terminal indicated by the higher layer signal.

4. The terminal according to claim 3, wherein

the transmission power control circuitry sets the transmission power of the uplink signal using one of a first power control and a second power control, based on a timing of reception of the TPC command and a timing of transmission of the uplink signal, and

the timing of reception of the TPC command and the timing of transmission of the uplink signal are based on the configuration of the terminal indicated by the higher layer signal.

5. A base station that communicates with a terminal, the base station comprising:

transmission circuitry that;

transmits a higher layer signal including a parameter to be used for uplink power control, the parameter indicating whether a subframe belongs to a first subframe set or a second subframe set, and the first subframe set being different from the second subframe set,

transmits a downlink control information (DCI) format including a transmission power control (TPC) command, the TPC command including a first power correction value in a case that the subframe belongs to the first subframe set, the TPC command including a second power correction value in a case that the subframe belongs to the second subframe, and the first power correction value being different from the second power correction value, wherein

the first power correction value or the second power correction value, which is included in the TPC command, is used for the terminal to set a transmission power of an uplink signal to be transmitted in the subframe to the base station.

6. A method of using a terminal, the method comprising:

receiving a higher layer signal including a parameter to be used for uplink power control, the parameter indicating whether a subframe belongs to a first subframe set or a second subframe set, and the first subframe set being different from the second subframe set;

detecting a transmission power control (TPC) command in a downlink control information (DCI) format and obtaining a power correction value from the TPC command, the TPC command including a first power correction value in a case that the subframe belongs to the first subframe set, the TPC command including a second power correction value in a case that the subframe belongs to the second subframe set, and the first power correction value being different from the second power correction value; and

setting a transmission power of an uplink signal to be transmitted in the subframe, based on the first power correction value or the second power correction value, which is included in the TPC command detected.