Carrier Grouping in Multicarrier Communications

• US 20140010215A1
• Filed: 09/03/2013
• Published: 01/09/2014
• 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
• Granted Patent: US 8,717,866 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• 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 a message assigning each second carrier to one of a first carrier group and second carrier group(s). The message comprises parameters for each second carrier. If the parameters comprise a carrier group index for a second carrier, the second carrier is assigned to one of the second carrier group(s) identified by the carrier group index. Otherwise, the second carrier is assigned to the first carrier group. The wireless device receives a time alignment command comprising the carrier group index and a time adjustment value.

Claims

1. 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 at least one or more processors, cause said wireless device to;

i) receive at least one message to cause assignment of each of at least one second carrier to one of a first carrier group and at least one second carrier group, said at least one message comprising a plurality of parameters for each of said at least one second carrier, wherein;

(1) if said plurality of parameters comprise a carrier group index for a second carrier, said second carrier is assigned to one of said at least one second carrier group identified by said carrier group index; and

(2) otherwise, said second carrier is assigned to said first carrier group; and

ii) receive a first time alignment command comprising said carrier group index and a time adjustment value.

2. The wireless device of claim 1, wherein:

a) said first carrier group comprises a first subset of a plurality of carriers; and

b) a second carrier group in said at least one second carrier group comprises a second subset of said at least one second carrier.

3. The wireless device of claim 2, wherein:

a) said plurality of carriers consist of a first carrier and said at least one second carrier;

b) said first subset comprises 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 timing reference; and

c) said second subset comprises a reference second carrier, uplink transmissions in said second carrier group employing a second synchronization signal on said reference second carrier as timing reference.

4. The wireless device of claim 3, wherein said reference second carrier is an activated carrier in said second carrier group.

5. The wireless device of claim 3, wherein said instructions further cause said wireless device to:

a) receive a control command configured to cause transmission of a random access preamble on random access resources of a carrier in said second carrier group; and

b) receive a random access response on said first carrier, said random access response comprising a second time alignment command for said second carrier group.

6. The wireless device of claim 5, wherein said instruction further cause said wireless device to transmit said random access preamble, transmission timing of said random access preamble being determined, at least in part, employing said reference second carrier.

7. The wireless device of claim 1, wherein said first time alignment command is configured to cause substantial alignment of reception timing of uplink signals in frames and subframes of a carrier group at said base station, said carrier group identified by said carrier group index.

8. A method for use in a wireless device, the method comprising:

a) receiving at least one message to cause assignment of each of at least one second carrier to one of a first carrier group and at least one second carrier group, said at least one message comprising a plurality of parameters for each of said at least one second carrier, wherein;

i) if said plurality of parameters comprise a carrier group index for a second carrier, said second carrier is assigned to one of said at least one second carrier group identified by said carrier group index; and

ii) otherwise, said second carrier is assigned to said first carrier group; and

b) receiving a first time alignment command comprising said carrier group index and a time adjustment value.

9. The method of claim 8, wherein:

a) said first carrier group comprises a first subset of a plurality of carriers; and

b) a second carrier group in said at least one second carrier group comprises a second subset of said at least one second carrier.

10. The method of claim 9, wherein:

a) said plurality of carriers consist of a first carrier and said at least one second carrier;

b) said first subset comprises 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 timing reference; and

c) said second subset comprises a reference second carrier, uplink transmissions in said second carrier group employing a second synchronization signal on said reference second carrier as timing reference.

11. The method of claim 8, wherein said first time alignment command is configured to cause substantial alignment of reception timing of uplink signals in frames and subframes of a carrier group at a base station, said carrier group identified by said carrier group index.

12. The method of claim 8, wherein said first carrier group is identified by a group index equal to zero.

13. The method of claim 8, wherein said at least one message is configured to further cause 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 time alignment command to adjust uplink transmission timing of a commanded carrier group in said plurality of carrier groups.

14. The method of claim 8, wherein said at least one message further comprises a time alignment timer parameter for each one of said first carrier group and said at least one second carrier group.

15. 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 at least one or more processors, cause said base station to;

i) transmit at least one message to cause assignment of each of at least one second carrier to one of a first carrier group and at least one second carrier group, said at least one message comprising a plurality of parameters for each of said at least one second carrier, wherein;

(1) if said plurality of parameters comprise a carrier group index for a second carrier, said second carrier is assigned to one of said at least one second carrier group identified by said carrier group index; and

(2) otherwise, said second carrier is assigned to said first carrier group; and

ii) transmit a first time alignment command comprising said carrier group index and a time adjustment value.

16. The base station of claim 15, wherein:

a) said first carrier group comprises a first subset of a plurality of carriers; and

b) a second carrier group in said at least one second carrier group comprises a second subset of said at least one second carrier.

17. The base station of claim 16, wherein:

a) said plurality of carriers consist of a first carrier and said at least one second carrier;

b) said first subset comprises 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 timing reference; and

c) said second subset comprises a reference second carrier, uplink transmissions in said second carrier group employing a second synchronization signal on said reference second carrier as timing reference.

18. The base station of claim 17, wherein said instructions further cause said base station to:

a) transmit a control command configured to cause transmission of a random access preamble on random access resources of a carrier in said second carrier group; and

b) transmit a random access response on said first carrier, said random access response comprising a second time alignment command for said second carrier group.

19. The base station of claim 18, wherein said instructions further cause said base station to receive said random access preamble, transmission timing of said random access preamble being determined, at least in part, employing said reference second carrier.

20. The base station of claim 15, wherein said first time alignment command is configured to cause substantial alignment of reception timing of uplink signals in frames and subframes of a carrier group at said base station, said carrier group identified by said carrier group index.