Transmit power control for physical random access channels

• US 9,008,050 B2
• Filed: 04/01/2011
• Issued: 04/14/2015
• Est. Priority Date: 04/01/2010
• Status: Active Grant

• Current Assignee: Sun Patent Trust
• Original Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Inventors: Feuersnger, Martin, Lhr, Joachim, Aoyama, Takahisa
• Primary Examiner(s): Vu, Huy D
• Assistant Examiner(s): CUNNINGHAM, KEVIN M
• Application Number:
  US13/637,607
• Publication Number:
  US 20130058315A1
• Time in Patent Office: 1,474 Days
• Field of Search: 370/336
• US Class Current: 370/336
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/281 taking into account user or data type priority
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 52/327 Power control of multicast channels
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 56/0045 compensating for timing error by altering transmission time
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

The invention relates to methods for adjusting the transmit power utilized by a mobile terminal for uplink transmissions, and to methods for adjusting the transmit power used by a mobile terminal for one or more RACH procedures. The invention is also providing apparatus and system for performing these methods, and computer readable media the instructions of which cause the apparatus and system to perform the methods described herein. In order to allow for adjusting the transmit power of uplink transmissions on uplink component carriers, the invention suggests introducing a power scaling for uplink PRACH transmissions performing RACH procedures on an uplink component carrier. The power scaling is proposed on the basis of a prioritization among multiple uplink transmissions or on the basis of the uplink component carriers on which RACH procedures are performed.

Claims

1. A terminal apparatus comprising:

a determining section configured to determine, for each subframe, power for physical uplink shared channel (PUSCH) transmission on a first component carrier which belongs to a first timing advance group (TAG), and to determine power for physical random access channel (PRACH) transmission on a second component carrier which belongs to a second TAG, the second TAG being different from the first TAG;

an adjusting section configured to adjust, when a total transmission power exceeds a maximum output power configured for the terminal apparatus P_MAX, the power for PUSCH transmission so that the adjusted total transmission power does not exceed P_MAX on an overlapped portion of the PUSCH transmission on a first subframe of the first component carrier and PRACH transmission on a second subframe of the second component carrier, the second subframe being a subframe with a time offset from the first subframe along a time axis, wherein the power for PRACH transmission is kept unadjusted; and

a transmitting section configured to transmit a transport block over the PUSCH of the first component carrier at the adjusted power for PUSCH transmission, and to transmit a random access preamble over the PRACH of the second component carrier at the determined power for PRACH transmission.

2. The terminal apparatus according to claim 1, wherein when transmitting the PUSCH simultaneously with a physical uplink control channel (PUCCH),

the determining section further determines power for PUCCH transmission;

and

the adjusting section adjusts at least one of the power for PUSCH transmission and the power for PUCCH transmission.

3. The terminal apparatus according to claim 2, wherein the adjusting section adjusts only the power for PUSCH transmission.

4. The terminal apparatus according to claim 1, wherein the PRACH transmission is initiated by a PDCCH order.

5. The terminal apparatus according to claim 1, wherein when transmission of the random access preamble is not requested and a physical uplink control channel (PUCCH) is transmitted simultaneously with the PUSCH,

the determining section sets the power for PRACH transmission to zero and further determines power for PUCCH transmission on the first component carrier;

and

the adjusting section adjusts the power for PUSCH transmission so that the adjusted total transmission power does not exceed P_MAX.

6. The terminal apparatus according to claim 1, wherein the adjusting section adjusts the power for PUSCH transmission per subframe.

7. The terminal apparatus according to claim 1, wherein when a plurality of PUSCHs are configured on the first component carrier, the adjusting section adjusts the power for PUSCH transmission by reducing respective powers for the plurality of PUSCHs.

8. The terminal apparatus according to claim 1, wherein the adjusting section adjusts the total transmission power in a priority order of the PRACH, the PUCCH and the PUSCH.

9. A power adjusting method comprising:

determining, for each subframe, power for physical uplink shared channel (PUSCH) transmission on a first component carrier which belongs to a first timing advance group (TAG), and determining power for physical random access channel (PRACH) transmission on a second component carrier which belongs to a second TAG, the second TAG being different from the first TAG;

adjusting, when a total transmission power exceeds a maximum output power configured for a terminal apparatus P_MAX, the power for PUSCH transmission so that the adjusted total transmission power does not exceed P_MAX on an overlapped portion of the PUSCH transmission on a first subframe of the first component carrier and the PRACH transmission on a second subframe of the second component carrier, the second subframe being a subframe with a time offset from the first subframe along a time axis, wherein the power for PRACH transmission is kept unadjusted; and

transmitting a transport block over the PUSCH of the first component carrier at the adjusted power for PUSCH transmission, and transmitting a random access preamble over the PRACH of the second component carrier at the determined power for PRACH transmission.

10. The power adjusting method according to claim 9, wherein when transmitting the PUSCH simultaneously with a physical uplink control channel (PUCCH) on the first component carrier, the method further comprising:

determining power for PUCCH transmission; and

adjusting at least one of the power for PUSCH transmission and the power for PUCCH transmission.

11. The power adjusting method according to claim 10, wherein the adjusting is performed by adjusting only the power for PUSCH transmission.

12. The power adjusting method according to claim 9, wherein the PRACH transmission is initiated by a PDCCH order.

13. The power adjusting method according to claim 9, wherein when transmission of the random access preamble is not requested and a physical uplink control channel (PUCCH) is transmitted simultaneously with the PUSCH, the method further comprising:

setting the power for PRACH transmission to zero and determining power for PUCCH transmission on the first component carrier; and

adjusting the power for PUSCH transmission so that the adjusted total transmission power does not exceed P_MAX.

14. The power adjusting method according to claim 9, wherein the adjusting is performed by adjusting the power for PUSCH transmission per subframe.

15. The power adjusting method according to claim 9, wherein when a plurality of PUSCHs are configured on the first component carrier, the adjusting includes adjusting the power for PUSCH transmission by reducing respective powers for the plurality of PUSCHs.

16. The power adjusting method according to claim 9, wherein the adjusting is performed by adjusting the total transmission power in a priority order of the PRACH, the PUCCH and the PUSCH.