Sounding in multicarrier wireless communications

1. A method comprising:

a) receiving, by a wireless device, at least one control message from a base station, said at least one control message causing in said wireless device:

i) configuration of a plurality of cells comprising a primary cell and at least one secondary cell;

ii) assignment of each of said at least one secondary cell to a cell group in a plurality of cell groups, said plurality of cell groups comprising

(1) a primary cell group comprising a first subset of said plurality of cells, said subset comprising said primary cell; and

(2) a secondary cell group comprising a second subset of said at least one secondary cell;

iii) configuration of transmissions of sounding reference signals on a first cell in said plurality of cells, said first cell being assigned to a first cell group in said plurality of cell groups, and

iv) configuration of at least one random access channel;

v) configuration of at least one data channel;

b) transmitting, by said wireless device, one or more of said sounding reference signals on said first cell in parallel with transmission of at least one of:

i) a first random access preamble; and

ii) a first uplink data packet; and

wherein a first sounding reference signal is one of said sounding reference signals, and said wireless device is configured to not transmit said first sounding reference signal on said first cell if at least one of the following conditions is satisfied:

(1) said first sounding reference signal transmission and a second random access preamble transmission in said first cell group coincide in the same subframe; and

(2) said wireless device has insufficient power to transmit said first sounding reference signal in parallel with at least one of:

(a) a third random access preamble, said third random access preamble transmission and said first sounding reference signal coincide in the same subframe; and

(b) a second uplink data packet transmission, said second uplink data packet transmission and said first sounding reference signal coincide in the same subframe; and

wherein said wireless device assigns said sounding reference signal transmission power a lower priority compared with a priority of a transmission power of said third random access preamble and a priority of a transmission power of said second uplink data packet transmission.

2. The method of claim 1 , wherein:

a) said first random access preamble is transmitted on one of said at least one random access channel; and

b) said first uplink data packet is transmitted on one of said at least one data channel.

3. The method of claim 1 , wherein said first cell group is one of:

a) said primary cell group; and

b) said secondary cell group.

4. The method of claim 1 , wherein said first cell group is out of sync when said second random access preamble is transmitted on said first cell group.

5. The method of claim 1 , wherein said first random access preamble is transmitted on a second cell of a second cell group, said second cell group being different from said first cell group.

6. The method of claim 1 , wherein said first uplink data packet is transmitted on a second cell of a second cell group, said second cell group being different from said first cell group.

7. The method of claim 1 , wherein said sounding reference signals are type zero sounding reference signals.

8. The method of claim 1 , wherein said sounding reference signals are configured to be transmitted during a time period.

9. The method of claim 1 , wherein said one or more of said sounding reference signals are transmitted on the last symbol of a plurality of subframes.

10. A wireless device comprising:

a) one or more communication interfaces;

b) one or more processors; and

c) memory storing instructions that, when executed, cause said wireless device:

i) receive at least one control message from a base station, said at least one control message causing in said wireless device:

(1) configuration of a plurality of cells comprising a primary cell and at least one secondary cell;

(2) assignment of each of said at least one secondary cell to a cell group in a plurality of cell groups; and

(3) configuration of transmissions of sounding reference signals on a first cell in said plurality of cells, said first cell being assigned to a first cell group in said plurality of cell groups; and

ii) transmit one or more of said sounding reference signals on said first cell in parallel with transmission of at least one of:

(1) a first random access preamble; and

(2) a first uplink data packet; and

wherein a first sounding reference signal is one of said sounding reference signals, and said wireless device is configured to not transmit said first sounding reference signal on said first cell if at least one of the following conditions is satisfied:

(1) said first sounding reference signal transmission and a second random access preamble transmission in said first cell group coincide in the same subframe; and

(2) said wireless device has insufficient power to transmit said first sounding reference signal in parallel with at least one of:

(a) a third random access preamble, said third random access preamble transmission and said first sounding reference signal coincide in the same subframe; and

(b) a second uplink data packet transmission, said second uplink data packet transmission and said first sounding reference signal coincide in the same subframe; and

wherein said wireless device assigns said sounding reference signal transmission power a lower priority compared with a priority of a transmission power of said third random access preamble and a priority of a transmission power of said second uplink data packet transmission.

11. The wireless device of claim 10 , wherein said first sounding reference signal transmission and a third uplink data packet transmission in said first cell group coincide in the same subframe.

12. The wireless device of claim 10 , wherein said first sounding reference signal transmission and an uplink physical control packet transmission in said first cell group coincide in the same subframe.

13. The wireless device of claim 10 , wherein said first cell group is out of sync when said second random access preamble is transmitted on said first cell group.

14. The wireless device of claim 10 , wherein said one or more of said sounding reference signals are transmitted on the last symbol of a plurality of subframes.