Sounding reference signal subframe position in a plurality of scheduled consecutive subframes

1. A method comprising:

receiving, by a wireless device, a radio resource control message comprising an aperiodic sounding reference signal (SRS) subframe parameter;

receiving a downlink control information:

indicating uplink resources in a plurality of scheduled consecutive subframes for transmission of transport blocks by the wireless device; and

triggering an SRS transmission in a subframe of the plurality of scheduled consecutive subframes; and

transmitting the SRS in the subframe, wherein a position of the subframe in the plurality of scheduled consecutive subframes is determined based on the aperiodic SRS subframe parameter.

2. The method of claim 1 , wherein the downlink control information comprises a first field indicating a number of the plurality of scheduled consecutive subframes.

3. The method of claim 1 , wherein the SRS is transmitted in more than one symbol of the subframe.

4. The method of claim 1 , wherein the aperiodic SRS subframe parameter indicates an offset from a starting subframe of the plurality of scheduled consecutive subframes.

5. The method of claim 1 , wherein the downlink control information comprises a listen-before-talk (LBT) configuration for an LBT procedure.

6. The method of claim 5 , wherein the SRS is based on the LBT procedure indicating a clear channel.

7. The method of claim 5 , wherein the LBT configuration indicates a symbol time interval is employed for the LBT procedure.

8. The method of claim 1 , wherein the downlink control information further comprises a field indicating whether transmission of the SRS is triggered.

9. The method of claim 1 , wherein the SRS is transmitted in a last symbol of the subframe.

10. The method of claim 1 , wherein the radio resource control message further comprise one or more common SRS parameters and one or more dedicated SRS parameters.

11. A wireless device comprising:

one or more processors; and

memory storing instructions that, when executed by the one or more processors, cause the wireless device to:

receive a radio resource control message comprising an aperiodic sounding reference signal (SRS) subframe parameter;

receive a downlink control information:

indicating uplink resources in a plurality of scheduled consecutive subframes for transmission of transport blocks by the wireless device; and

triggering an SRS transmission in a subframe of the plurality of scheduled consecutive subframes; and

transmit the SRS in the subframe, wherein a position of the subframe in the plurality of scheduled consecutive subframes is determined based on the aperiodic SRS subframe parameter.

12. The wireless device of claim 11 , wherein the downlink control information comprises a first field indicating a number of the plurality of scheduled consecutive subframes.

13. The wireless device of claim 11 , wherein the SRS is transmitted in more than one symbol of the subframe.

14. The wireless device of claim 11 , wherein the aperiodic SRS subframe parameter indicates an offset from a starting subframe of the plurality of scheduled consecutive subframes.

15. The wireless device of claim 11 , wherein the downlink control information comprises a listen-before-talk (LBT) configuration for an LBT procedure.

16. The wireless device of claim 15 , wherein the SRS is based on the LBT procedure indicating a clear channel.

17. The wireless device of claim 15 , wherein the LBT configuration indicates a symbol time interval is employed for the LBT procedure.

18. The wireless device of claim 11 , wherein the downlink control information further comprises a field indicating whether transmission of the SRS is triggered.

19. The wireless device of claim 11 , wherein the SRS is transmitted in a last symbol of the subframe.

20. A system comprising:

a base station comprising:

one or more first processors; and

first memory storing first instructions that, when executed by the one or more first processors, cause the base station to:

transmit a radio resource control message comprising an aperiodic sounding reference signal (SRS) subframe parameter;

transmit a downlink control information; and

a wireless device comprising:

one or more second processors; and

second memory storing second instructions that, when executed by the one or more second processors, cause the wireless device to:

receive the radio resource control message;

receive the downlink control information, wherein the downlink control information:

indicates uplink resources in a plurality of scheduled consecutive subframes for transmission of transport blocks by the wireless device; and

triggers an SRS transmission in a subframe of the plurality of scheduled consecutive subframes; and

transmit the SRS in the subframe, wherein a position of the subframe in the plurality of scheduled consecutive subframes is determined based on the aperiodic SRS subframe parameter.