Transmission Timing in a Carrier Group

• US 20140177623A1
• Filed: 03/02/2014
• Published: 06/26/2014
• 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 9,391,824 B2
• Time in Patent Office: Days
• US Class Current: 370/350
• 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

Transmission timing of a random access preamble in an uplink carrier of a carrier group being determined employing a synchronization signal transmitted on a downlink carrier of the carrier group. The wireless device receives a time alignment command from the base station. The time alignment command comprises a time adjustment value and an index identifying the carrier group. The wireless device applies the time adjustment value to uplink signals transmitted on any activated uplink carriers in the carrier group.

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 one or more processors, cause said wireless device to;

i) receive at least one radio resource control message comprising;

(1) configuration parameters of a first carrier and at least one second carrier; and

(2) a carrier group index for a second carrier in said at least one second carrier, said carrier group index identifying a second carrier group, said second carrier group being one of a plurality of carrier groups, said second carrier group comprising a second subset of said at least one second carrier;

ii) receive a control command causing said wireless device to transmit a random access preamble on said second carrier;

iii) transmit said random access preamble on said second carrier, transmission timing of said random access preamble being determined, at least in part, employing a second synchronization signal transmitted on a downlink carrier in said second carrier group, uplink transmissions in said second carrier group employing said second synchronization signal as timing reference;

iv) receive a time alignment command comprising a time adjustment value and an index identifying said second carrier group; and

v) apply said time adjustment value to uplink signals transmitted on any activated carrier in said second carrier group.

2. The wireless device of claim 1, wherein said control command is received on the scheduling carrier of said second carrier.

3. The wireless device of claim 2, wherein said control command further comprises a carrier index identifying said second carrier.

4. The wireless device of claim 1, wherein said control command further comprises a power control command.

5. The wireless device of claim 1, wherein said control command is scrambled using and identifier of said wireless device.

6. The wireless device of claim 1, wherein said control command is received in response to said wireless device transmitting a buffer status report to said base station, said buffer status report comprising a buffer size, said buffer size indicating an amount of data available for transmission in the buffers of said wireless device.

7. The wireless device of claim 1, wherein said control command further comprises a mask index employed by said wireless device to determine transmission timing or transmission resources of said random access preamble.

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

a) receiving at least one radio resource control message comprising;

i) configuration parameters of a first carrier and at least one second carrier; and

ii) a carrier group index for a second carrier in said at least one second carrier, said carrier group index identifying a second carrier group, said second carrier group being one of a plurality of carrier groups, said second carrier group comprising a second subset of said at least one second carrier;

b) receiving a control command causing said wireless device to transmit a random access preamble on said second carrier;

c) transmitting said random access preamble on said second carrier, transmission timing of said random access preamble being determined, at least in part, employing a second synchronization signal transmitted on a downlink carrier in said second carrier group, uplink transmissions in said second carrier group employing said second synchronization signal as timing reference;

d) receiving a time alignment command comprising a time adjustment value and an index identifying said second carrier group; and

e) applying said time adjustment value to uplink signals transmitted on any activated carrier in said second carrier group.

9. The method of claim 8, wherein said control command is received on the scheduling carrier of said second carrier.

10. The method of claim 9, wherein said control command further comprises a carrier index identifying said second carrier.

11. The method of claim 8, wherein said control command further comprises a power control command.

12. The method of claim 8, wherein said control command is scrambled using and identifier of said wireless device.

13. The method of claim 8, wherein said control command is transmitted in response to said wireless device transmitting a buffer status report to said base station, said buffer status report comprising a buffer size, said buffer size indicating an amount of data available for transmission in the buffers of said wireless device.

14. The method of claim 8, wherein said control command further comprises a mask index employed by said wireless device to determine transmission timing or transmission resources of said random access preamble.

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 one or more processors, cause said base station to;

i) transmit at least one radio resource control message comprising;

(1) configuration parameters of a first carrier and at least one second carrier; and

(2) a carrier group index for a second carrier in said at least one second carrier, said carrier group index identifying a second carrier group, said second carrier group being one of a plurality of carrier groups, said second carrier group comprising a second subset of said at least one second carrier;

ii) transmit a control command causing said wireless device to transmit a random access preamble on said second carrier;

iii) receive said random access preamble on said second carrier, transmission timing of said random access preamble being determined, at least in part, employing a second synchronization signal transmitted on a downlink carrier in said second carrier group, uplink transmissions in said second carrier group employing said second synchronization signal as timing reference;

iv) transmit a time alignment command comprising a time adjustment value and an index identifying said second carrier group; and

wherein said time alignment command causes substantial alignment of reception timing of uplink signals in frames and subframes of said second carrier group.

16. The base station of claim 15, wherein said control command is transmitted on the scheduling carrier of said second carrier.

17. The base station of claim 16, wherein said control command further comprises a carrier index identifying said second carrier.

18. The base station of claim 15, wherein said control command further comprises a power control command.

19. The base station of claim 15, wherein said control command is scrambled using and identifier of said wireless device.

20. The base station of claim 15, wherein said control command is transmitted in response to said wireless device transmitting a buffer status report to said base station, said buffer status report comprising a buffer size, said buffer size indicating an amount of data available for transmission in the buffers of said wireless device.