Sounding reference signal

• US 8,625,404 B2
• Filed: 05/05/2013
• Issued: 01/07/2014
• Est. Priority Date: 07/25/2011
• Status: Active Grant

• Current Assignee: Comcast Cable Communications LLC (Comcast Corporation)
• Original Assignee: Ofinno Technologies, LLC
• Inventors: Dinan, Esmael Hejazi
• Primary Examiner(s): HSU, ALPUS
• Application Number:
  US13/887,347
• Publication Number:
  US 20130242958A1
• Time in Patent Office: 247 Days
• Field of Search: 370/206, 370/252, 370/329, 370/350, 375/260, 375/356, 455/450, 455/502
• US Class Current: 370/206
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2657 Carrier synchronisation
• CPC Class Codes: H04L 27/2666 Acquisition of further OFDM parameters, e.g. bandwidth, subcarrier spacing, or guard interval length
• CPC Class Codes: H04L 27/2692 with preamble design, i.e. with negotiation of the synchronisation sequence with transmitter or sequence linked to the algorithm used at the receiver
• CPC Class Codes: H04L 5/0085 when channel conditions change
• CPC Class Codes: H04L 5/0098 Signalling of the activation or deactivation of component carriers, subcarriers or frequency bands
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks
• CPC Class Codes: H04W 56/0045 compensating for timing error by altering transmission time
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/008 with additional processing of random access related information at receiving side
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

A wireless device receives RRC message(s) configuring transmissions of sounding reference signals on a second carrier in a second carrier group. The wireless device receives a random access response comprising a long time alignment value and a preamble identifier. The wireless device transmits the sounding reference signals on the second carrier after adjusting uplink transmission timing of the second carrier group. The wireless device is configured to not transmit any of the sounding reference signals on the second carrier until the wireless device receives the random access response comprising the long time alignment value and an uplink grant.

Claims

1. A method comprising:

a) receiving, by a wireless device, at least one radio resource control (RRC) message from a base station, said at least one RRC message causing in said wireless device;

i) configuration of a plurality of carriers comprising a first carrier and at least one second carrier;

ii) assignment of a second carrier to a second carrier group in a plurality of carrier groups, said plurality of carrier groups comprising;

(1) a first carrier group comprising a first subset of said plurality of carriers, said first subset comprising said first carrier, uplink transmissions by said wireless device in said first carrier group employing a first synchronization signal transmitted on said first carrier as a first timing reference; and

(2) said second carrier group comprising a second subset of said at least one second carrier; and

iii) configuration of transmissions of sounding reference signals on said second carrier in said second carrier group;

b) receiving, by said wireless device, an activation command to activate said second carrier in said wireless device;

c) receiving, by said wireless device, a control command configured to cause transmission of a random access preamble on random access resources of one of said at least one second carrier in said second subset;

d) receiving, by said wireless device, a random access response, said random access response comprising a long time alignment value for said second carrier group and a preamble identifier; and

e) transmitting, by said wireless device, one or more of said sounding reference signals on said second carrier after adjusting uplink transmission timing of said second carrier group based on said long time alignment value, said wireless device configured to not transmit any of said sounding reference signals on said second carrier until said wireless device receives said random access response comprising said long time alignment value and an uplink grant.

2. The method of claim 1, wherein said uplink grant comprises power control information.

3. The method of claim 2, further comprising applying said power control information to uplink signals before transmitting said one or more of said sounding reference signals.

4. The method of claim 1, wherein said adjusting uplink transmission timing causes substantial alignment of reception timing of uplink signals in frames and subframes of said second carrier group at said base station.

5. The method of claim 1, wherein said at least one RRC message causes configuration of said random access resources.

12. The wireless device of claim 4, wherein said uplink grant comprises power control information.

13. The wireless device of claim 12, wherein said instructions, when executed, further cause said wireless device to apply said power control information to uplink signals before transmitting said one or more of said sounding reference signals.

6. A base station comprising:

a) one or more communication interfaces configured to communicate with a wireless device via at least one wireless link;

b) one or more processors; and

c) memory storing instructions that, when executed by said one or more processors, cause said base station to;

i) transmit at least one radio resource control (RRC) message to said wireless device, said at least one RRC message is configured to cause in said wireless device;

(1) configuration of a plurality of carriers comprising a first carrier and at least one second carrier;

(2) assignment of a second carrier to a second carrier group in a plurality of carrier groups, said plurality of carrier groups comprising;

(a) a first carrier group comprising a first subset of said plurality of carriers, said first subset comprising said first carrier; and

(b) said second carrier group comprising a second subset of said at least one second carrier; and

(3) configuration of transmissions of sounding reference signals on said second carrier in said second carrier group; and

ii) transmit a control command configured to cause transmission of a random access preamble on random access resources of one of said at least one second carrier in said second subset;

iii) transmit a random access response, said random access response comprising a long time alignment value for said second carrier group and a preamble identifier; and

iv) receive one or more of said sounding reference signals on said second carrier after uplink transmission timing of said second carrier group is adjusted based on said long time alignment value, wherein said base station does not receive any of said sounding reference signals on said second carrier until said random access response comprising said long time alignment value and an uplink grant is transmitted by said base station.

7. The base station of claim 6, wherein said at least one RRC message is configured to further cause in said wireless device configuration of a time alignment timer for each of said plurality of carrier groups, said time alignment timer starting or restarting in response to said wireless device receiving a timing alignment command to adjust uplink transmission timing of a commanded carrier group in said plurality of carrier groups.

8. The base station of claim 6, wherein said at least one RRC message comprises a plurality of parameters comprising a time alignment timer parameter for each carrier group in said plurality of carrier groups.

9. The base station of claim 6, wherein adjusting uplink transmission timing causes substantial alignment of reception timing of uplink signals in frames and subframes of said second carrier group at said base station.

10. The base station of claim 6, wherein uplink transmissions by said wireless device in said first carrier group employ a first synchronization signal transmitted on said first carrier.

11. A wireless device comprising:

a) one or more communication interfaces configured to communicate with a base station via at least one wireless link;

b) one or more processors; and

c) memory storing instructions that, when executed by said one or more processors, cause said wireless device to;

i) receive at least one radio resource control (RRC) message from said base station, said at least one RRC message causing in said wireless device;

(1) configuration of a plurality of carriers comprising a first carrier and at least one second carrier;

(2) assignment of a second carrier to a second carrier group in a plurality of carrier groups, said plurality of carrier groups comprising;

(a) a first carrier group comprising a first subset of said plurality of carriers, said first subset comprising said first carrier; and

(b) said second carrier group comprising a second subset of said at least one second carrier; and

(3) configuration of transmissions of sounding reference signals on said second carrier in said second carrier group; and

ii) receive a control command configured to cause transmission of a random access preamble on random access resources of one of said at least one second carrier in said second subset;

iii) receive a random access response, said random access response comprising a long time alignment value for said second carrier group and a preamble identifier; and

iv) transmit one or more of said sounding reference signals on said second carrier after adjusting uplink transmission timing of said second carrier group based on said long time alignment value, said wireless device configured to not transmit any of said sounding reference signals on said second carrier until said wireless device receives said random access response comprising said long time alignment value and an uplink grant.

14. The wireless device of claim 11, wherein said adjusting uplink transmission timing causes substantial alignment of reception timing of uplink signals in frames and subframes of said second carrier group at said base station.