SOUNDING REFERENCE SIGNAL TRANSMISSION IN CARRIER AGGREGATION

• US 20160233996A1
• Filed: 02/08/2016
• Published: 08/11/2016
• Est. Priority Date: 09/17/2010
• Status: Active Grant

• Current Assignee: Blackberry Limited
• Original Assignee: Blackberry Limited
• Inventors: HEO, Youn Hyoung, FONG, Mo-Han, BUCKLEY, Michael Eoin, EARNSHAW, Andrew Mark, CAI, Zhijun
• Granted Patent: US 9,876,618 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0066 Requirements on out-of-channel emissions
• CPC Class Codes: H04L 5/0078 Timing of allocation
• CPC Class Codes: H04L 5/0096 Indication of changes in allocation
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A cell-specific sounding reference symbol (SRS) subframe configuration and UE-specific SRS configuration are defined for carrier aggregation. For the cell-specific SRS subframe configuration, the same cell-specific SRS subframes are configured for all uplink (UL) carrier components (CCs). For the UE-specific SRS configuration, different configurations are applied for UL CCs. Also, to reduce signaling overhead, the different UE-specific SRS configuration is signaled by using an offset on top of the UE-specific SRS configuration of a primary component carrier (PCC).

Claims

1. A method for transmitting a sounding reference symbol (SRS) comprising:

applying a SRS configuration for a plurality of uplink component carriers (UL CCs),

transmitting a SRS via uplink subframes.

2. The method of claim 1 wherein:

the SRS configuration comprises at least one of a cell-specific sounding reference symbol (SRS) subframe configuration and a user equipment (UE) specific SRS configuration.

3. The method of claim 2 wherein:

for the cell-specific SRS subframe configuration, particular cell-specific SRS subframes are configured for all uplink (UL) component carriers (CCs).

4. The method of claim 2 wherein:

for the UE-specific SRS configuration, different configurations are applied for uplink (UL) component carriers (CCs).

5. The method of claim 4 wherein:

a UE-specific SRS configuration is signaled via an offset on top of a UE-specific SRS configuration of a primary component carrier (PCC).

6. An apparatus for transmitting a sounding reference symbol (SRS) comprising:

a processor;

memory coupled to the processor, the memory storing instructions executable by the processor for;

applying a SRS configuration for a plurality of uplink component carriers (UL CCs),

transmitting a SRS via uplink subframes.

7. A method for transmitting a sounding reference symbol (SRS) comprising:

applying a SRS configuration for a plurality of uplink component carriers (UL CCs); and

,

reducing a transmit power when SRS and other uplink channels are simultaneously transmitted in multiple uplink (UL) component carriers (CCs) and a total transmit power exceeds the maximum allowed power.

8. The method of claim 17 wherein:

reducing the transmit power comprises applying an equal scaling operation to the SRS and a physical uplink shared channel (PUSCH).

9. The method of claim 18 wherein:

the equal scaling operation comprises applying a signaled ratio to the SRS and a physical uplink shared channel (PUSCH).

10. The method of claim 18 wherein:

the equal scaling operation is applied at a subframe.

11. The method of claim 18 wherein:

the equal scaling operation is applied at a last SC-FDMA symbol where SRS is transmitted.

12. The method of claim 17 wherein:

reducing the transmit power comprises scaling down only the PUSCH power.

13. The method of claim 17 wherein:

reducing the transmit power comprises puncturing a last symbol in a subframe of PUSCH where SRS is also transmitted.

14. The method of claim 17 wherein:

reducing the transmit power comprises scaling down only the SRS transmission power.

15. The method of claim 17 wherein:

reducing the transmit power comprises dropping the SRS signal.

16. An apparatus for transmitting a sounding reference symbol (SRS) comprising:

a processor;

memory coupled to the processor, the memory storing instructions executable by the processor for;

receiving and applying a sounding reference symbol (SRS) configuration for a plurality of uplink component carriers (UL CCs); and

,

controlling the transmit power of the UE when SRS and other uplink channels are simultaneously transmitted in multiple uplink (UL) component carriers (CCs) and a total transmit power exceeds the maximum allowed power.