Grant-less operations
Current approaches to transmitting uplink data in a network often require resources to be granted. In an example, a node or apparatus may configure a plurality of devices to operate in a grant-less mode in accordance with a respective grant-less access allocation. Grant-less operations may be managed, for example, to meet the reliability and latency requirements and battery life requirements for different types of devices. For example, the state transition between grant-less and grant based may be managed.
1. An apparatus comprising a processor, a memory, and communication circuitry, the apparatus being connected to an access network via its communication circuitry, the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform operations comprising:
receiving an indication of one or more access allocations for grant-less transmissions;
selecting an access allocation of the one or more access allocations so as to define a selected access allocation;
determining a first transmit power level for a grant-less transmission;
transmitting, at the first transmit power level, an uplink message over the selected access allocation without requesting an uplink grant, so as to transmit a grant-less transmission;
determining whether to retransmit the uplink message; and
if the uplink message is retransmitted in a retransmission:
determining whether to switch to an uplink grant mode for the retransmission;
determining a second power level for the retransmission; and
making the retransmission at the second power level, using the uplink grant mode or a grant-less retransmission.
2. The apparatus as recited in claim 1 , the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform further operations comprising:
determining to retransmit the uplink message in response to a grant-less transmission timer expiring.
3. The apparatus as recited in claim 1 , the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform further operations comprising:
receiving a transition direction from the access network; and
determining to retransmit the uplink message based on the transition direction from the access network.
4. The apparatus as recited in claim 1 , the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform further operations comprising:
receiving a transition direction from the access network; and
based on the transition direction from the access network, determining to switch to the grant mode, so as to transition from a grant-less mode to the uplink grant mode based on the transition direction from the access network.
5. The apparatus as recited in claim 4 , wherein receiving the transition direction comprises receiving the transition direction on a down link control channel for the grant-less transmission.
6. The apparatus as recited in claim 4 , wherein the transition direction comprises the uplink grant.
7. The apparatus as recited in claim 1 , the apparatus further comprising a physical layer, a high layer above the physical layer, and further computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform further operations comprising:
based on a direction from the high layer, determining to request the uplink grant mode for the retransmission, so as to transition from a grant-less mode to the grant mode based on the direction from the high layer.
8. The apparatus as recited in claim 1 , wherein determining first the transmit power level comprises performing a path loss estimation.
9. The apparatus as recited in claim 8 , the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform further operations comprising:
receiving a synchronization signal or a reference signal from the access network; and
using the synchronization signal or the reference signal to perform the path loss estimation.
10. The apparatus as recited in claim 1 , wherein determining the first transmit power level further comprises performing a modulation and coding scheme for the grant-less transmission.
11. The apparatus as recited in claim 1 , the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform further operations comprising:
receiving a power control direction from the access network; and
adjusting the first transmit power level based on the power control direction, so as to define new transmit power level for a subsequent grant-less transmission.
12. The apparatus as recited in claim 1 , the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform further operations comprising:
receiving a power control direction from the access network; and
adjusting the first transmit power level based on the power control direction, so as to define the second transmit power level for the retransmission.
13. The apparatus as recited in claim 12 , wherein receiving the power control direction further comprises receiving the power control direction from a down link control channel for grant-less transmit power control.
14. An apparatus comprising a processor, a memory, and communication circuitry, the apparatus being connected to a user equipment via its communication circuitry, the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform operations comprising:
sending an indication of one or more access allocations for grant-less transmissions;
sending synchronization signals and/or reference signals;
receiving an uplink grant-less message over one of the one or more access allocations without sending an uplink grant, so as to receive an uplink grant-less message;
determining a power level adjustment based on the received uplink grant-less message;
determining whether to request for a retransmission of the uplink grant-less message; and
if the uplink grant-less message is requested for retransmission:
determining whether the retransmission should be in a grant mode; and
sending a retransmission indication comprising the power level adjustment.
15. The apparatus as recited in claim 14 , the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform further operations comprising:
determining that the uplink message should be retransmitted in the grant mode; and
allocating an uplink grant in the retransmission indication so as to indicate the grant mode.
16. A method perform by a user equipment during grant-less operation, the method comprising:
receiving an indication of one or more access allocations for grant-less transmissions;
selecting an access allocation of the one or more access allocations so as to define a selected access allocation;
determining a first transmit power level for a grant-less transmission;
transmitting, at the first transmit power level, an uplink message over the selected access allocation without requesting an uplink grant, so as to;
determining whether to retransmit the uplink message; and
if the uplink message is retransmitted in a retransmission:
determining whether to switch to an uplink grant mode for the retransmission;
determining a second power level for the retransmission; and
making the retransmission at the second power level, using the uplink grant mode or a grant-less retransmission.