WIRELESS COMMUNICATION DEVICE AND METHOD FOR CONTROLLING TRANSMISSION POWER

• US 20130040689A1
• Filed: 04/27/2011
• Published: 02/14/2013
• Est. Priority Date: 04/30/2010
• Status: Active Grant

• Current Assignee: Sun Patent Trust
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Iwai, Takashi, Imamura, Daichi, Nishio, Akihiko, Ogawa, Yoshihiko, Takaoka, Shinsuke
• Granted Patent: US 9,055,535 B2
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 72/0473 the resource being transmission power
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Disclosed is a wireless communication device that can suppress an increase in power consumption of a terminal while preventing the degradation of SINR measurement precision resulting from TPC errors in a base station. A terminal (100) controls the transmission power of a second signal by adding an offset to the transmission power of a first signal; an offset-setting unit (106) sets an offset correction value in response to a transmission time gap between a third signal transmitted the previous time and the second signal transmitted this time; and a transmission power control unit (111) controls the transmission power of the second signal using the correction value.

Claims

1. A radio communication apparatus that adds an offset value to transmission power of a first signal to control transmission power of a second signal, the apparatus comprising:

a control section that controls the transmission power of the second signal using the offset value determined according to a transmission period of the second signal; and

a transmission section that transmits the second signal with the transmission power controlled in the control section.

2. The radio communication apparatus according to claim 1, wherein the offset value is determined such that the transmission power of the second signal in the case where the second signal has a short transmission period is lower than the transmission power of the second signal in the case where the second signal has a long transmission period.

3. The radio communication apparatus according to claim 1, wherein the offset value is determined according to whether the transmission period is set to the second signal.

4. The radio communication apparatus according to claim 3, wherein the offset value is determined such that the transmission power of the second signal to which the transmission period thereof is set is lower than the transmission power of the second signal to which the transmission period thereof is not set.

5. The radio communication apparatus according to claim 1, further comprising a plurality of antennas,

wherein the control section controls the respective transmission power of each of a plurality of the second signals using the respective offset values corresponding to the plurality of second signals transmitted from the respective antennas, the offset values being determined according to the transmission periods of the second signals in the respective antennas.

6. The radio communication apparatus according to claim 1, further comprising:

a plurality of antennas; and

a setting section that determines the offset values corresponding to a plurality of the second signals transmitted from the respective antennas according to the transmission periods of the second signals in the respective antennas,

wherein the control section controls the respective transmission power of each of the plurality of second signals using a ratio of the offset value corresponding to each of the plurality of second signals, the ratio of the offset value being a ratio of the transmission power assigned to each of the plurality of second signals to total transmission power, the total transmission power being power assigned to all the second signals transmitted from the respective antennas and being calculated by adding the offset value to the transmission power of the first signal.

7. The radio communication apparatus according to claim 1, wherein the first signal is a signal transmitted through a physical uplink shared channel (PUSCH), and the second signal is a sounding reference signal (SRS).

8. The radio communication apparatus according to claim 1, wherein the second signal to which the transmission period thereof is not set is a sounding reference signal (SRS) transmitted only once after reception of a trigger signal from a base station apparatus.

9. A radio communication apparatus that derives channel quality of a second signal from channel quality of a first signal using an offset value, the apparatus comprising:

a reception section that receives the first signal; and

a channel quality deriving section that derives the channel quality of the second signal from the channel quality of the first signal, using the offset value determined according to a transmission period of the second signal.

10. A method of controlling transmission power in a radio communication apparatus that adds an offset value to transmission power of a first signal to control transmission power of a second signal, the method comprising:

controlling the transmission power of the second signal using the offset value determined according to a transmission period of the second signal.

11. A method of deriving channel quality that derives channel quality of a second signal from channel quality of a first signal using an offset value to, the method comprising:

deriving the channel quality of the second signal using the offset value determined according to a transmission period of the second signal.