Uplink signal starting position in a wireless device and wireless network
A wireless device receives one or more messages comprising configuration parameters of a licensed assisted access (LAA) cell. The wireless device receives a downlink control information (DCI) for the LAA cell. The DCI may comprise a first field and a second field. The first field indicates uplink resources for an uplink subframe of the LAA cell. The second field indicates a first starting position in a plurality of starting positions in the uplink subframe. The first starting position in the uplink subframe is determined, at least, based on a sum of twenty-five micro-seconds plus a timing advance value. The wireless device constructs one or more transport blocks employing the DCI. The wireless device transmits the one or more transport blocks in the uplink resources starting from the first starting position of the uplink subframe.
1. A method comprising:
receiving, by a wireless device, one or more messages comprising configuration parameters of a licensed assisted access (LAA) cell;
receiving a downlink control information (DCI) for the LAA cell, the DCI comprising:
a first field indicating uplink resources for an uplink subframe of the LAA cell; and
a second field indicating a first starting position in a plurality of starting positions in the uplink subframe, wherein the first starting position in the uplink subframe is determined, at least, based on a sum of twenty-five micro-seconds plus a timing advance value;
constructing one or more transport blocks employing the DCI; and
transmitting, by the wireless device, the one or more transport blocks in the uplink resources starting from the first starting position of the uplink subframe.
2. The method of claim 1 , wherein the second field comprises two bits of information.
3. The method of claim 1 , further comprising, performing, by the wireless device, a listen-before-talk (LBT) process for the twenty-five micro-seconds.
4. The method of claim 1 , wherein the plurality of starting positions comprises:
a beginning of symbol zero;
a beginning of symbol one; and
twenty-five micro-seconds after the beginning of symbol zero.
5. The method of claim 1 , wherein the uplink subframe starts earlier than a downlink subframe by the timing advance value.
6. The method of claim 1 , wherein the wireless device does not transmit any uplink signals on the LAA cell during a gap period before the first starting position.
7. The method of claim 1 , further comprising receiving, by the wireless device, a full downlink subframe in a subframe proceeding the uplink subframe.
8. The method of claim 1 , further comprising receiving, by the wireless device, a partial downlink subframe in a subframe proceeding the uplink subframe.
9. The method of claim 1 , wherein the DCI is a dedicated DCI.
10. The method of claim 1 , further comprising:
receiving, by the wireless device, a timing advance command comprising the timing advance value; and
adjusting uplink transmission timing for one or more uplink channels based on the timing advance value.
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 one or more messages comprising configuration parameters of a licensed assisted access (LAA) cell;
receive a downlink control information (DCI) for the LAA cell, the DCI comprising:
a first field indicating uplink resources for an uplink subframe of the LAA cell; and
a second field indicating a first starting position in a plurality of starting positions in the uplink subframe, wherein the first starting position in the uplink subframe is determined, at least, based on a sum of twenty-five micro-seconds plus a timing advance value;
construct one or more transport blocks employing the DCI; and
transmit the one or more transport blocks in the uplink resources starting from the first starting position of the uplink subframe.
12. The wireless device of claim 11 , wherein the second field comprises two bits of information.
13. The wireless device of claim 11 , wherein the instructions, when executed by the one or more processors, further cause the wireless device to perform a listen-before-talk (LBT) process for the twenty-five micro-seconds.
14. The wireless device of claim 11 , wherein the plurality of starting positions comprises:
a beginning of symbol zero;
a beginning of symbol one; and
twenty-five micro-seconds after the beginning of symbol zero.
15. The wireless device of claim 11 , wherein the uplink subframe starts earlier than a downlink subframe by the timing advance value.
16. The wireless device of claim 11 , wherein the wireless device does not transmit any uplink signals on the LAA cell during a gap period before the first starting position.
17. The wireless device of claim 11 , wherein the instructions, when executed by the one or more processors, further cause the wireless device to receive a full downlink subframe in a subframe proceeding the uplink subframe.
18. The wireless device of claim 11 , wherein the instructions, when executed by the one or more processors, further cause the wireless device to receive a partial downlink subframe in a subframe proceeding the uplink subframe.
19. The wireless device of claim 11 , wherein the DCI is a dedicated DCI.
20. The wireless device of claim 11 , wherein the instructions, when executed by the one or more processors, further cause the wireless device to:
receive a timing advance command comprising the timing advance value; and
adjust uplink transmission timing for one or more uplink channels based on the timing advance value.