Method for aperiodic SRS subframe configuration and signaling

1. A method for operating a user equipment (UE) based on a sounding reference signal (SRS) subframe configuration, the method comprising:

defining user equipment (UE) specific Aperiodic Sounding Reference Signal (A-SRS) subframes within a radio subframe;

performing a state base operation when defining the UE specific A-SRS subframes; and

using, by the user equipment (UE), the UE specific A-SRS subframes,

wherein the state base operation comprises configuring the UE with a periodicity and an offset within a set of cell specific SRS subframes of a radio frame, and

wherein when a certain period is configured, the UE can schedule A-SRS in all cell specific SRS subframes in a radio frame, and

when another period is configured, only one subframe can be scheduled within a set of cell specific SRS subframes in a radio frame for A-SRS transmission.

2. The method of claim 1 further comprising:

performing a bit map operation when defining the UE specific A-SRS subframes.

3. The method of claim 2 wherein:

the bit map operation comprises using a predetermined number of bits for the UE-specific A-SRS subframe configuration and associating each bit with one subframe within a radio frame.

4. The method of claim 3 wherein:

when an n th bit is assigned a predefined value, then an n th subframe in a system frame is configured as an A-SRS subframe for the UE.

5. The method of claim 3 wherein:

when an n th bit corresponds to a subframe that is not configured as a cell specific SRS subframe, the n th bit is used to perform error detection and correction of the bit map operation.

6. The method of claim 3 wherein:

when an n th bit corresponds to a subframe that is not configured as a cell specific SRS subframe, the n th bit is used to carry additional information.

7. The method of claim 1 wherein:

a maximum period is related to the radio frame.

8. The method of claim 1 wherein:

a minimum offset is defined for the radio frame.

9. A method for sounding reference signal (SRS) subframe configuration comprising:

indicating to a particular User Equipment (UE) a set of UE-specific Aperiodic Sounding Reference Signal (A-SRS) subframes that are configured for the particular UE by:

(1) transmitting to the particular UE a first indication of which subframe in set Si is the initial subframe in the set of UE-specific subframes; and

(2) transmitting to the particular UE a second indication that each pth (P e {1, 2, . . . , 9}) subframe after the initial subframe in the set of UE-specific subframes in set Si is also included in the set of UE-specific subframes such that the particular UE utilizes the UE-specific A-SRS subframe configuration for signaling;

wherein the state base operation comprises configuring the UE with a periodicity and an offset within a set of cell specific SRS subframes of a radio frame, and

wherein when a certain period is configured, the UE can schedule A-SRS in all cell specific SRS subframes in a radio frame, and

when another period is configured, only one subframe can be scheduled within a set of cell specific SRS subframes in a radio frame for A-SRS transmission.

10. A method for sounding reference signal (SRS) subframe configuration comprising:

transmitting to a particular User Equipment (UE) an index value; and

using the index value at the particular UE to determine values Astart and Ainc, where Astart indicates which subframe in set Si is a starting subframe to include in a set of UE-specific A-SRS subframes and Ainc indicates that each subframe after the starting subframe in set Si that is separated by an integer multiple of Ainc is also included in the set of UE-specific A-SRS subframes, such that the particular UE utilizes the UE-specific A-SRS subframe configuration for signaling;

wherein the state base operation comprises configuring the UE with a periodicity and an offset within a set of cell specific SRS subframes of a radio frame, and

wherein when a certain period is configured, the UE can schedule A-SRS in all cell specific SRS subframes in a radio frame, and

when another period is configured, only one subframe can be scheduled within a set of cell specific SRS subframes in a radio frame for A-SRS transmission.