Random access mechanism for a wireless device and base station

• US 9,386,604 B2
• Filed: 01/15/2015
• Issued: 07/05/2016
• Est. Priority Date: 04/01/2012
• Status: Active Grant

• Current Assignee: Comcast Cable Communications LLC (Comcast Corporation)
• Original Assignee: Ofinno Technologies, LLC
• Inventors: Dinan, Esmael Hejazi
• Primary Examiner(s): KAMARA, MOHAMED A
• Application Number:
  US14/597,468
• Publication Number:
  US 20150139140A1
• Time in Patent Office: 537 Days
• Field of Search: 370/310, 370/324, 370/350, 370/395.62, 370328-329, 370338-339, 370/341, 455443-444, 455/446, 455448-450, 455/464, 455/502, 455524-525
• US Class Current: 1/1
• CPC Class Codes: H04L 27/261 Details of reference signals
• CPC Class Codes: H04L 27/2662 Symbol synchronisation
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/22 taking into account previous information or commands
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

A wireless device receives control message(s) comprising parameters of a plurality of cell groups and a pathloss reference for each secondary cell. The wireless device transmits uplink signals in a first secondary cell in a secondary cell group. Transmission power of the uplink signals is determined employing a received power of the pathloss reference assigned to the first secondary cell. Timing of the uplink signals in the secondary cell group employs a synchronization signal on an active secondary cell in the secondary cell group as a timing reference.

Claims

1. A wireless device comprising:

one or more processors; and

memory storing instructions that, when executed, cause the wireless device to;

receive at least one message comprising;

configuration parameters of a plurality of cells comprising a primary cell and at least one secondary cell, the plurality of cells being grouped into a plurality of cell groups comprising a primary cell group and a secondary cell group; and

a pathloss reference for each secondary cell in the at least one secondary cell, the pathloss reference being only configurable as a downlink of the secondary cell if the secondary cell is in the secondary cell group;

autonomously select an activated cell as a timing reference cell in the secondary cell group; and

transmit uplink signals in a first secondary cell of the secondary cell group, wherein;

transmission power of the uplink signals is determined employing a first pathloss reference configured for the first secondary cell; and

timing of the uplink signals is derived employing the timing reference cell.

2. The wireless device of claim 1, wherein:

the primary cell group comprises a first subset of the plurality of cells, the first subset comprising the primary cell, uplink transmission timing in the first cell group being derived employing the primary cell; and

the secondary cell group comprises a second subset of the at least one secondary cell.

3. The wireless device of claim 1, wherein the instructions, when executed, further cause the wireless device to stop transmission of uplink transport blocks in the secondary cell group if the following conditions are satisfied:

the wireless device is unable to acquire timing of the timing reference cell; and

the secondary cell group does not comprise any other active cells except the timing reference cell.

4. The wireless device of claim 3, wherein the instructions, when executed, further cause the wireless device to allow uplink transmission of at least one random access preamble in the secondary cell group if the conditions are satisfied.

5. The wireless device of claim 3, wherein the instructions, when executed, further cause the wireless device to continue transmission of channel state information for the timing reference cell on an uplink carrier not belonging to the secondary cell group if the conditions are satisfied.

6. The wireless device of claim 1, wherein the timing reference cell is different from the pathloss reference.

7. The wireless device of claim 1, wherein the instructions, when executed, further cause the wireless device to autonomously select a new activated secondary cell in the secondary cell group as a new timing reference cell if the following conditions are satisfied:

the wireless device is unable to acquire timing of the timing reference cell; and

at least one secondary cell, different from the timing reference cell, in the secondary cell group is active in the wireless device.

8. The wireless device of claim 1, wherein the instructions, when executed, further cause the wireless device to receive at least one control packet comprising one or more power control commands, transmission power of a plurality of packets transmitted by the wireless device being calculated employing, at least in part:

a received power of the pathloss reference configured for the first secondary cell; and

the one or more power control commands.

9. The wireless device of claim 1, wherein the instructions, when executed, further cause the wireless device to stop transmission of uplink transport blocks on the first secondary cell if the wireless device is unable to measure a received power of the pathloss reference for a period of time.

10. The wireless device of claim 1, wherein the transmission power of the uplink signals is determined, at least in part, further employing at least one power control parameter received in the at least one control message.

11. The wireless device of claim 1, wherein the transmission power of the uplink signals is determined, at least in part, employing measurements of a received power of the pathloss reference assigned to the first secondary cell.

12. A method comprising:

receiving, by a wireless device, at least one message comprising;

configuration parameters of a plurality of cells comprising a primary cell and at least one secondary cell, the plurality of cells being grouped into a plurality of cell groups comprising a primary cell group and a secondary cell group; and

a pathloss reference for each secondary cell in the at least one secondary cell, the pathloss reference being only configurable as a downlink of the secondary cell if the secondary cell is in the secondary cell group;

autonomously selecting, by the wireless device, an activated cell as a timing reference cell in the secondary cell group; and

transmitting uplink signals in a first secondary cell of the secondary cell group, wherein;

transmission power of the uplink signals is determined employing a first pathloss reference configured for the first secondary cell; and

timing of the uplink signals is derived employing the timing reference cell.

13. The method of claim 12, wherein:

the primary cell group comprises a first subset of the plurality of cells, the first subset comprising the primary cell, uplink transmission timing in the first cell group being derived employing the primary cell; and

the secondary cell group comprises a second subset of the at least one secondary cell.

14. The method of claim 12, further comprising stopping transmission of uplink transport blocks in the secondary cell group if the following conditions are satisfied:

the wireless device is unable to acquire timing of the timing reference cell; and

the secondary cell group does not comprise any other active cells except the timing reference cell.

15. The method of claim 14, further comprising allowing uplink transmission of at least one random access preamble in the secondary cell group if the conditions are satisfied.

16. The method of claim 14, further comprising continuing transmission of channel state information for the timing reference cell on an uplink carrier not belonging to the secondary cell group if the conditions are satisfied.

17. The method of claim 12, wherein the timing reference cell is different from the pathloss reference.

18. The method of claim 12, further comprising autonomously selecting a new activated secondary cell in the secondary cell group as a new timing reference cell if the following conditions are satisfied:

the wireless device is unable to acquire timing of the timing reference cell; and

at least one secondary cell, different from the timing reference cell, in the secondary cell group is active in the wireless device.

19. The method of claim 12, further comprising receiving at least one control packet comprising one or more power control commands, transmission power of a plurality of packets transmitted by the wireless device being calculated employing, at least in part:

a received power of the pathloss reference configured for the first secondary cell; and

the one or more power control commands.

20. The method of claim 12, further comprising stopping transmission of uplink transport blocks on the first secondary cell if the wireless device is unable to measure a received power of the pathloss reference for a period of time.