Uplink transmissions via a license assisted cell in a wireless network
View Patent ↗A wireless device receives downlink control information comprising: an allocation of resource blocks for transmission of uplink data via a subframe of a LAA cell; a first field comprising an index indicating a starting position for the transmission of the uplink data, the index identifying one of pre-configured starting positions; and a second field indicating an ending symbol for the transmission of the uplink data, the ending symbol being one of pre-configured ending symbols. A listen-before-talk procedure indicating a clear channel is performed before the starting position of the subframe. Based at least on the starting position and the ending symbol, the uplink data to resource elements corresponding to the resource blocks are mapped. The uplink data is transmitted, via the LAA cell, starting at the starting position in the subframe and ending before the ending symbol.
1. A method comprising:
receiving, by a wireless device, a downlink control information comprising:
an allocation of resource blocks for transmission of uplink data via a subframe of a licensed assisted access (LAA) cell;
a first field comprising an index indicating a starting position for the transmission of the uplink data, the index identifying one of pre-configured starting positions; and
a second field indicating an ending symbol for the transmission of the uplink data, the ending symbol being one of pre-configured ending symbols;
performing, before the starting position of the subframe, a listen-before-talk procedure indicating a clear channel;
mapping, based at least on the starting position and the ending symbol, the uplink data to resource elements corresponding to the resource blocks; and
transmitting, the uplink data via the LAA cell, starting at the starting position in the subframe and ending before the ending symbol.
2. The method of claim 1 , wherein the subframe is a starting subframe of a multi-subframe burst.
3. The method of claim 1 , wherein the transmitting the uplink data further comprises:
transmitting a reservation signal until an allowed symbol for a physical uplink shared channel transmission; and
transmitting data symbols starting from the allowed symbol.
4. The method of claim 3 , wherein a duration of the reservation signal is less than one symbol.
5. The method of claim 1 , wherein the starting position is based on a value of an uplink timing advance calculated by a wireless device.
6. The method of claim 1 , wherein the downlink control information comprises a listen-before-talk parameter.
7. The method of claim 1 , wherein the downlink control information comprises a transmit power control command.
8. The method of claim 1 , further comprising receiving uplink transmission parameters for the LAA cell.
9. The method of claim 1 , wherein the downlink control information indicates a starting time for the listen-before-talk procedure.
10. The method of claim 1 , wherein a starting time for the listen-before-talk procedure is at a pre-determined time before the starting position.
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 downlink control information comprising:
an allocation of resource blocks for transmission of uplink data via a subframe of a licensed assisted access (LAA) cell;
a first field comprising an index indicating a starting position for the transmission of the uplink data, the index identifying one of pre-configured starting positions; and
a second field indicating an ending symbol for the transmission of the uplink data, the ending symbol being one of pre-configured ending symbols;
perform, before the starting position of the subframe, a listen-before-talk procedure indicating a clear channel;
map, based at least on the starting position and the ending symbol, the uplink data to resource elements corresponding to the resource blocks; and
transmit, the uplink data via the LAA cell, starting at the starting position in the subframe and ending before the ending symbol.
12. The wireless device of claim 11 , wherein the subframe is a starting subframe of a multi-subframe burst.
13. The wireless device of claim 11 , wherein the instructions, when transmitting the uplink data, further cause the wireless device to:
transmit a reservation signal until a first allowed symbol for a physical uplink shared channel transmission; and
transmit data symbols starting from the first allowed symbol.
14. The wireless device of claim 13 , wherein a duration of the reservation signal is less than one symbol.
15. The wireless device of claim 11 , wherein the starting position is based on a value of an uplink timing advance calculated by the wireless device.
16. The wireless device of claim 11 , wherein the downlink control information comprises a listen-before-talk parameter.
17. The wireless device of claim 11 , wherein the downlink control information comprises a transmit power control command.
18. The wireless device of claim 11 , wherein configuration parameters for the LAA cell comprise uplink transmission parameters.
19. The wireless device of claim 11 , wherein the downlink control information indicates a starting time for the listen-before-talk procedure.
20. The wireless device of claim 11 , wherein a starting time for the listen-before-talk procedure is at a pre-determined time before the starting position.