Communications device, infrastructure equipment and methods
A communications device configured to receive data from an infrastructure equipment of a wireless communications network is provided. The communications device comprises transceiver circuitry configured to transmit signals and to receive signals via a wireless access interface provided by the wireless communications network, and controller circuitry. The controller circuitry is configured to control the transceiver circuitry to receive an explicit uplink hybrid automatic repeat request acknowledgement indicator, e-HARQ indicator, from the infrastructure equipment, and to determine, in accordance with the received e-HARQ indicator, whether or not the communications device should monitor for a first HARQ acknowledgement, HARQ-ACK, in a specific time slot and in a specific frequency resource of the wireless access interface, the first HARQ-ACK being transmitted by the infrastructure equipment in response to an uplink transmission from the communications device to the infrastructure equipment.
1. An infrastructure equipment forming part of a wireless communications network, the infrastructure equipment, comprising:
transceiver circuitry configured to transmit signals and to receive signals via a wireless access interface provided by the wireless communications network, and
controller circuitry configured to control the transceiver circuitry to
transmit an explicit uplink hybrid automatic repeat request acknowledgement indicator, e-HARQ indicator, to a communications device,
wherein the e-HARQ indicator indicates to the communications device whether or not the communications device should monitor for a first HARQ acknowledgement, HARQ-ACK, in a specific time slot and in a specific frequency resource of the wireless access interface, the first HARQ-ACK being transmitted by the infrastructure equipment in response to an uplink transmission from the communications device to the infrastructure equipment,
wherein the specific time slot in which the communications device should monitor for the first HARQ-ACK is one of a plurality of consecutive time slots forming a time window.
2. The infrastructure equipment according to claim 1 , wherein the controller circuitry is configured to control the transceiver circuitry to
transmit, as downlink control information, DCI, to the communications device, an uplink grant indicating resources of the wireless access interface that the communications device should use for the uplink transmission to the infrastructure equipment,
wherein the uplink grant comprises the e-HARQ indicator.
3. The infrastructure equipment according to claim 1 , wherein the controller circuitry is configured to control the transceiver circuitry to
transmit, as group common DCI to the communications device, a Slot Format Indicator indicating a configuration of one or more time divided slots of a wireless access interface provided by the wireless communications network for transmitting data to the communications device on the downlink or receiving data from the communications device on the uplink,
wherein the Slot Format Indicator comprises the e-HARQ indicator.
4. The infrastructure equipment according to claim 1 , wherein the controller circuitry is configured to control the transceiver circuitry to
transmit a radio resource control, RRC, configuration message from the wireless communications network, the RRC configuration message comprising the e-HARQ indicator.
5. The infrastructure equipment according to claim 4 , wherein the controller circuitry is configured to control the transceiver circuitry to
transmit, to the communications device, a Slot Form Indicator, SFI, the SFI indicating a configuration of one or more time divided slots of a wireless access interface provided by the wireless communications network for transmitting data to the communications device on the downlink or receiving data from the communications device on the uplink,
wherein the SFI is provided by one of the RRC configuration message, an SFI communicated in a group communications channel and DCI, and
wherein the transmitted e-HARQ indicator is dependent on at least one parameter of the transmitted SFI.
6. The infrastructure equipment according to claim 5 , wherein the at least one parameter of the transmitted SFI is the configuration of the one or more time divided slots of the wireless access interface.
7. The infrastructure equipment according to claim 4 , wherein the controller circuitry is configured to control the transceiver circuitry to
transmit, to the communications device, an uplink grant indicating resources of the wireless access interface that the communications device should use for the uplink transmission to the infrastructure equipment,
wherein the transmitted e-HARQ indicator is dependent on at least one parameter of the transmitted uplink grant.
8. The infrastructure equipment according to claim 7 , wherein the at least one parameter of the transmitted uplink grant is an identifier of a HARQ process used by the infrastructure equipment to transmit a HARQ-ACK to the communications device in response to the uplink transmission.
9. The infrastructure equipment according to claim 7 , wherein the at least one parameter of the transmitted uplink grant is a time delay between the transmission of the uplink grant by the infrastructure equipment and the transmission of the uplink transmission by the communications device.
10. The infrastructure equipment according to claim 7 , wherein the at least one parameter of the transmitted uplink grant is a transport block size, TBS, scheduled by the uplink grant.
11. The infrastructure equipment according to claim 7 , wherein the at least one parameter of the transmitted uplink grant is a granularity used by the communications device to monitor the wireless access interface for the uplink grant from the infrastructure equipment.
12. The infrastructure equipment according to claim 1 , wherein the specific time slot in which the communications device should monitor for the first HARQ-ACK is predetermined and is known to the communications device.
13. The infrastructure equipment according to claim 1 , wherein the specific time slot in which the communications device should monitor for the first HARQ-ACK is indicated in an RRC configuration message transmitted to the communications device from the infrastructure equipment.
14. The infrastructure equipment according to claim 1 , wherein the controller circuitry is configured to control the transceiver circuitry to
transmit, to the communications device, an uplink grant indicating resources of the wireless access interface that the communications device should use for the uplink transmission to the infrastructure equipment,
wherein the specific time slot in which the communications device should monitor for the first HARQ-ACK is indicated in the uplink grant.
15. The infrastructure equipment according to claim 1 , wherein the specific frequency resource in which the communications device should monitor for the first HARQ-ACK is indicated in an RRC configuration message transmitted to the communications device from the infrastructure equipment.
16. The infrastructure equipment according to claim 1 , wherein the specific frequency resource in which the communications device should monitor for the first HARQ-ACK contains a physical hybrid ARQ indicator channel, PHICH,
wherein the PHICH comprises a single bit indicating a positive acknowledgement or a negative acknowledgement.
17. The infrastructure equipment according to claim 1 , wherein the specific frequency resource in which the communications device should monitor for the first HARQ-ACK contains an uplink grant indicating resources of the wireless access interface that the communications device should use for the uplink transmission to the infrastructure equipment.
18. A method of operating an infrastructure equipment forming part of a wireless communications network, the method, comprising;
transmitting an explicit uplink hybrid automatic repeat request acknowledgement indicator, e-HARQ indicator, to a communications device,
wherein the e-HARQ indicator indicates to the communications device whether or not the communications device should monitor for a first HARQ acknowledgement, HARQ-ACK, in a specific time slot and in a specific frequency resource of a wireless access interface provided by the wireless communications network, the first HARQ-ACK being transmitted by the infrastructure equipment in response to an uplink transmission from the communications device to the infrastructure equipment,
wherein the specific time slot in which the communications device should monitor for the first HARQ-ACK is one of a plurality of consecutive time slots forming a time window.
19. Circuitry for an infrastructure equipment forming part of a wireless communications network, the infrastructure equipment, comprising:
transceiver circuitry configured to transmit signals and to receive signals via a wireless access interface provided by the wireless communications network, and
controller circuitry configured to control the transceiver circuitry to
transmit an explicit uplink hybrid automatic repeat request acknowledgement indicator, e-HARQ indicator, to a communications device,
wherein the e-HARQ indicator indicates to the communications device whether or not the communications device should monitor for a first HARQ acknowledgement, HARQ-ACK, in a specific time slot and in a specific frequency resource of the wireless access interface, the first HARQ-ACK being transmitted by the infrastructure equipment in response to an uplink transmission from the communications device to the infrastructure equipment,
wherein the specific time slot in which the communications device should monitor for the first HARQ-ACK is one of a plurality of consecutive time slots forming a time window.