Methods, communications device and non-terrestrial network infrastructure equipment

1 . A method of operating a communications device to transmit or to receive via a non-terrestrial network, NTN, infrastructure equipment, the method comprising:

detecting, by transceiver circuitry of the communications device, signals from the NTN infrastructure equipment during one of a plurality of in-coverage periods during which the communications device is in a coverage area of the NTN infrastructure equipment because the communications device can receive signals either

transmitted from the NTN infrastructure equipment carried by an aerial vehicle, or

relayed from the NTN infrastructure equipment via the aerial vehicle as the aerial vehicle passes over the communications device;

identifying, based on a determined profile of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected, one or more sub-periods of a subsequent in-coverage period subsequent to the one of the plurality of in-coverage periods during which a communication of data can provide a relative reduction in an amount of communications resources required to correctly communicate the data compared with other sub-periods of the subsequent in-coverage period; and

transmitting signals carrying the data in the one or more sub-periods of the subsequent in-coverage period based on the identification, or

receiving signals carrying the data in the one or more sub-periods of the subsequent in-coverage period based on the identification.

2 . The method according to claim 1 , comprising:

determining, from the detected signals, the determined profile of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected by the communications device,

transmitting a representation of the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods, and

receiving, from the NTN infrastructure equipment, scheduling information identifying the one or more sub-periods of the subsequent in-coverage period subsequent to the one of the plurality of in-coverage periods during which the communication of data can provide the relative reduction in the amount of communications resources required to correctly communicate the data compared with the other sub-periods of the subsequent in-coverage period.

3 . The method according to claim 2 , wherein the representation of the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods is derived from an estimation of a reference signal received power, RSRP, a measured pathloss of the detected signals, or a representation of channel state information.

4 . The method according to claim 2 , wherein the representation of the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods is determined by:

estimating a free space pathloss throughout the one of the plurality of in-coverage periods,

calculating a pathloss of the detected signals between the NTN infrastructure equipment and the communications device which includes the free space pathloss and an additional pathloss, and

determining the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods by subtracting the estimated free space pathloss from the calculated pathloss.

5 . The method according to claim 2 , further comprising:

determining, from the detected signals, an identifier of the aerial vehicle carrying the NTN infrastructure equipment, and

transmitting the identifier to a wireless communications network via the NTN infrastructure equipment, whereby the wireless communications network can schedule transmission or reception of data using the NTN infrastructure equipment carried by the aerial vehicle and one or more other NTN infrastructure equipment carried by one or more other aerial vehicles.

6 . The method according to claim 5 , wherein the identifier of the aerial vehicle carrying the NTN infrastructure equipment is an identity of a cell that is transmitted via the aerial vehicle.

7 . The method according to claim 1 , further comprising:

determining, from the detected signals, the determined profile of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected by the communications device,

from the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods, determining at least one sub-period of the subsequent in-coverage period subsequent to the one of the plurality of in-coverage periods during which the communication of data can provide the relative reduction in the amount of communications resources required to correctly communicate the data compared with the other sub-periods of the subsequent in-coverage period,

transmitting an indication of the determined at least one sub-period of the subsequent in-coverage period subsequent to the one of the plurality of in-coverage periods to a wireless communications network in which the wireless communications network can schedule a transmission or reception of the data, and

receiving, from the NTN infrastructure equipment, scheduling information identifying time and frequency resources from the one or more sub-periods of the subsequent in-coverage period subsequent to the one of the plurality of in-coverage periods based on the indicated at least one sub-period of the subsequent in-coverage period subsequent to the one of the plurality of in-coverage periods during which the communication of data can provide the relative reduction in the amount of communications resources required to correctly communicate the data compared with the other sub-periods of the subsequent in-coverage period.

8 . The method according to claim 7 , further comprising:

determining, from the detected signals, an identifier of the aerial vehicle carrying the NTN infrastructure equipment, and

transmitting the identifier to the wireless communications network via the NTN infrastructure equipment, whereby the wireless communications network can schedule transmission or reception of data using the NTN infrastructure equipment carried by the aerial vehicle and one or more other NTN infrastructure equipment carried by one or more other aerial vehicles.

9 . The method according to claim 7 , wherein the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods is determined by

estimating a free space pathloss throughout the one of the plurality of in-coverage periods,

calculating a pathloss of the detected signals between the NTN infrastructure equipment and the communications device which includes the free space pathloss and an additional pathloss, and

determining the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods by subtracting the estimated free space pathloss from the calculated pathloss.

10 . The method according to claim 2 , further comprising:

determining one or more of the sub-periods in which the communications device would prefer to transmit or to receive signals,

receiving signals representing downlink data from the NTN infrastructure equipment for which an acknowledgement signal is requested, and

transmitting an indication of the preferred one or more sub-periods to the NTN infrastructure equipment with the requested acknowledgement signal.

11 . The method according to claim 2 , wherein the transmitting the representation of the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods in-coverage-period-comprises;

determining that the communications device has not moved since detecting the signals from the NTN infrastructure equipment during one of the plurality of in-coverage periods, and

in response,

transmitting the representation of the determined profile with respect to time within the one of the plurality of in-coverage periods.

12 . The method according to claim 2 , further comprising:

determining whether the communications device has moved since receiving the scheduling information, and

if the communications device has moved,

transmitting an indication to a wireless communications network indicating that the determined profile of channel conditions with respect to time within the one of the plurality of in-coverage periods is no longer valid.

13 . The method according to claim 2 , wherein the transmitting the representation of the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods comprises;

transmitting the representation of the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods in a Radio Resource Control (RRC) signal, Channel State Information (CSI) signal, or as part of an initial access procedure to a base station.

14 . The method according to claim 1 , further comprising:

determining, from the detected signals, the determined profile of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected by the communications device, and

based on the determined profile of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected, transmitting a physical random access preamble in the one or more sub-periods of the subsequent in-coverage period to the NTN infrastructure equipment.

15 . The method according to claim 1 , wherein the detecting, by transceiver circuitry of the communications device, the signals from the NTN infrastructure equipment comprises:

detecting signals from the NTN infrastructure equipment during the one of the plurality of in-coverage periods during which the communications device is in the coverage area of the NTN infrastructure equipment and can receive the signals from the NTN infrastructure equipment as the NTN infrastructure equipment carried by the aerial vehicle passes over the communications device,

detecting signals from one or more other NTN infrastructure equipment during one of a plurality of in-coverage periods for each of the one or more other NTN infrastructure equipment during which the communications device is in a coverage area of the one or more other NTN infrastructure equipment and can receive signals from the one or more other NTN infrastructure equipment as the one or more other NTN infrastructure equipment carried by one or more other aerial vehicles pass over the communications device, and

based on the determined profile of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected and one or more other determined profiles of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the one or more other NTN infrastructure equipment have been detected,

selecting to transmit or receive signals carrying the data via one of the NTN infrastructure equipment and the one or more other NTN infrastructure equipment which can provide the relative reduction in the amount of communications resources required to correctly communicate the data carried by the signals compared with others of the NTN infrastructure equipment and the one or more other NTN infrastructure equipment.

16 . The method according to claim 1 , further comprising:

configuring, based on the determined profile of the channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected, a profile of the channel conditions with respect to positions of the aerial vehicle relative to the communications device during the one of the plurality of in-coverage periods, wherein

the transmitting the signals carrying the data in the one or more sub-periods of the subsequent in-coverage period based on the identification comprises

determining, based on the profile of the channel conditions with respect to the positions of the aerial vehicle relative to the communications device during the one of the plurality of in-coverage periods, positions of the aerial vehicle relative to the communications device during the one or more sub-periods during which a transmission of signals by the communications device can provide the relative reduction in the amount of communications resources required to correctly communicate the data carried by the transmitted signals compared with the other sub-periods of the subsequent in-coverage period; and

transmitting the signals carrying data when the aerial vehicle occupies the determined positions, and

the receiving the signals carrying the data in the one or more sub-periods of the subsequent in-coverage period based on the identification comprises

determining, based on the profile of the channel conditions with respect to the positions of the aerial vehicle relative to the communications device during the one of the plurality of in-coverage periods, positions of the aerial vehicle relative to the communications device during the one or more sub-periods during which a reception of signals by the communications device transmitted by the NTN infrastructure equipment can provide the relative reduction in the amount of communications resources required to correctly communicate the data carried by the received signals compared with the other sub-periods of the subsequent in-coverage period; and

receiving the signals carrying data when the aerial vehicle occupies the determined positions.

17 . The method according to claim 1 , further comprising:

based on the determined profile of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected,

identifying the one or more sub-periods of the subsequent in-coverage period subsequent to the one of the plurality of in-coverage periods during which transmission or reception of signals by the communications device can provide a relative increase in a likelihood of correctly communicating data by the transmitted or received signals compared with the other sub-periods of the subsequent in-coverage period, and

configuring a Machine-Type Communication (MTC) Physical Downlink Control Channel (MPDCCH) or NB-IoT PDCCH (NPDCCH) search space formed from a set of candidates of MPDCCH/NPDCCH resources and parameters as a function of the determined profile of channel conditions with respect to time by using candidates having a lower number of repetitions in the identified one or more sub-periods compared with the other sub-periods of the subsequent in-coverage period.

18 . The method according to claim 1 , further comprising using fewer demodulation reference signals (DMRS) in the identified one or more sub-periods compared with the other sub-periods of the subsequent in-coverage period.

19 . A communications device configured to transmit or to receive via a non-terrestrial network, NTN, infrastructure equipment, the communications device comprising:

transceiver circuitry configured to transmit or to receive signals; and

control circuitry configured in combination with the transceiver circuitry to

detect signals from the NTN infrastructure equipment during one of a plurality of in-coverage periods during which the communications device is in a coverage area of the NTN infrastructure equipment because the communications device can receive signals either

transmitted from the NTN infrastructure equipment carried by an aerial vehicle, or

relayed from the NTN infrastructure equipment via the aerial vehicle as the aerial vehicle passes over the communications device,

identify, based on a determined profile of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected, one or more sub-periods of a subsequent in-coverage period subsequent to the one of the plurality of in-coverage periods during which a communication of data can provide a relative reduction in an amount of communications resources required to correctly communicate the data compared with other sub-periods of the subsequent in-coverage period, and

transmit signals carrying the data in the one or more sub-periods of the subsequent in-coverage period based on the identification, or

receive signals carrying the data in the one or more sub-periods of the subsequent in-coverage period based on the identification.

20 . A non-terrestrial network, NTN, infrastructure equipment of a wireless communications network configured to transmit to or receive from one or more communications devices, the NTN infrastructure equipment comprising:

transceiver circuitry configured to transmit or to receive signals; and

control circuitry configured in combination with the transceiver circuitry to

receive from a communications device, a profile of channel conditions with respect to time within one of a plurality of in-coverage periods in which signals from the NTN infrastructure equipment have been detected by the communications device while the communications device is in a coverage area of the NTN infrastructure equipment because the communications device can receive signals either transmitted from the NTN infrastructure equipment carried by an aerial vehicle or relayed from the NTN infrastructure equipment via the aerial vehicle as the aerial vehicle passes over the communications device,

identify, based on the received profile of channel conditions with respect to time within the one of the plurality of in-coverage periods in which the signals from the NTN infrastructure equipment have been detected, one or more sub-periods of a subsequent in-coverage period subsequent to the one of the plurality of in-coverage periods during which a communication of data can provide a relative reduction in an amount of communications resources required to correctly communicate the data compared with other sub-periods of the subsequent in-coverage period, and

transmit signals carrying the data in the one or more sub-periods of the subsequent in-coverage period based on the identification, or

receive signals carrying the data in the one or more sub-periods of the subsequent in-coverage period based on the identification.