Method and device for communicating with a selected transport block size

1. Circuitry for a communications device, the circuitry comprising:

transceiver circuitry; and

controller circuitry configured in combination with the transceiver circuitry to:

receive, from infrastructure equipment in a wireless communications system, a scheduling message comprising an indication of an allocation of radio resources to be used for a random access procedure message for a random access procedure supported by the wireless communications system;

select a transport block size (TBS) from a plurality of permitted TBS values for transmission of the random access procedure message, wherein each permitted TBS value of the plurality of permitted TBS values is associated with a repetition number, the repetition number being a maximum number of times that the random access procedure message can be transmitted in the allocated radio resources for the each permitted TBS value of the plurality of permitted TBS values;

determine whether the selected TBS is lower than a maximum TBS of the plurality of permitted TBS values; and

in a case that the selected TBS is determined to be lower than the maximum TBS:

select, based on an identifier of the communications device, a starting transmission time for starting transmission of the random access procedure message from a set of one or more permitted starting transmission times associated with the selected TBS; and

transmit the random access procedure message to the infrastructure equipment in the allocated radio resources using the selected TBS at the selected starting transmission time.

2. The circuitry according to claim 1 , wherein the controller circuitry selects the starting transmission time by randomly selecting the starting transmission time from the set of one or more permitted starting transmission times.

3. The circuitry according to claim 1 , wherein the controller circuitry selects the starting transmission time by selecting a default starting transmission time from the set of one or more permitted starting transmission times.

4. The circuitry according to claim 3 , wherein the controller circuitry is further configured in combination with the transceiver circuitry circuitry to:

receive, from the infrastructure equipment, an indication that the communications device is permitted to select the default starting transmission time or any one of the starting transmission times other than the default starting transmission time from the set of one or more permitted starting transmission times; and

select the default starting transmission time or any one of the starting transmission times other than the default starting transmission time.

5. The circuitry according to claim 1 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to receive, from the infrastructure equipment, an indication that the random access procedure message should be retransmitted.

6. The circuitry according to claim 5 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to:

receive, from the infrastructure equipment, an allocation of a set of radio resources to be used for retransmission of the random access procedure message, the set of radio resources being allocated by the infrastructure equipment based on the selected TBS for the transmission of the random access procedure message; and

retransmit the random access procedure message to the infrastructure equipment in the set of radio resources using the selected TBS.

7. The circuitry according to claim 5 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to:

receive, from the infrastructure equipment, an allocation of a set of radio resources to be used for retransmission of the random access procedure message, the set of radio resources being large enough for the random access procedure message to be transmitted using the maximum TBS;

receive an indication that the repetition number, that should be used for the retransmission of the random access procedure message, should be associated with the maximum TBS; and

retransmit the random access procedure message to the infrastructure equipment in the set of radio resources using the selected TBS and the repetition number associated with the selected TBS.

8. The circuitry according to claim 5 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to:

receive, from the infrastructure equipment, an allocation of a set of radio resources to be used for retransmission of the random access procedure message, the set of radio resources being large enough for the random access procedure message to be transmitted using the maximum TBS;

receive an indication of a repetition number that should be used for the retransmission of the random access procedure message; and

retransmit the random access procedure message to the infrastructure equipment in the set of radio resources using the selected TBS and the indicated repetition number.

9. The circuitry according to claim 5 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to:

receive, from the infrastructure equipment, an allocation of a set of radio resources to be used for retransmission of the random access procedure message, the set of radio resources being large enough for the random access procedure message to be transmitted using the selected TBS;

receive an indication of a repetition number that should be used for the retransmission of the random access procedure message; and

retransmit the random access procedure message to the infrastructure equipment in the set of radio resources using the selected TBS and the indicated repetition number.

10. The circuitry according to claim 5 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to:

receive, from the infrastructure equipment, an allocation of a set of radio resources to be used for retransmission of the random access procedure message;

receive an indication that the maximum TBS should be used for the retransmission of the random access procedure message; and

retransmit the random access procedure message to the infrastructure equipment in the set of radio resources using the selected TBS and the repetition number associated with the selected TBS.

11. The circuitry according to claim 5 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to:

receive, from the infrastructure equipment, an allocation of a set of radio resources to be used for retransmission of the random access procedure message;

receive an indication that the maximum TBS should be used for the retransmission of the random access procedure message;

receive an indication of a repetition number that should be used for the retransmission of the random access procedure message;

apply a scaling factor to the indicated repetition number to generate a scaled repetition number, the scaling factor having been applied to the repetition number associated with the selected TBS for the initial transmission of the random access procedure message; and

retransmit the random access procedure message to the infrastructure equipment in the set of radio resources using the selected TBS and the scaled repetition number.

12. The circuitry according to claim 5 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to:

receive, from the infrastructure equipment, an allocation of a set of radio resources to be used for retransmission of the random access procedure message;

receive an indication that the selected TBS should be used for the retransmission of the random access procedure message; and

retransmit the random access procedure message to the infrastructure equipment in the set of radio resources using the selected TBS and the repetition number associated with the selected TBS.

13. The circuitry according to claim 5 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to:

receive, from the infrastructure equipment, an allocation of a set of radio resources to be used for retransmission of the random access procedure message;

receive, from the infrastructure equipment, an indication that the communications device should retransmit the random access procedure message using a different starting transmission time from the selected starting transmission time; and

retransmit the random access procedure message to the infrastructure equipment in the set of radio resources using the selected TBS and the repetition number associated with the selected TBS at another starting transmission time from the set of one or more permitted starting transmission times associated with the selected TBS other than the selected starting transmission time for the transmission of the random access procedure message.

14. The circuitry according to claim 5 , wherein the controller circuitry is further configured in combination with the transceiver circuitry to:

receive, from the infrastructure equipment, an allocation of a set of radio resources to be used for retransmission of the random access procedure message;

generate a random number;

compare the random number with a probability threshold; and

retransmit the random access procedure message to the infrastructure equipment in the set of radio resources using the selected TBS and the repetition number associated with the selected TBS, wherein

dependent on a comparison, the random access procedure message is retransmitted at another starting transmission time from the set of one or more permitted starting transmission times associated with the selected TBS other than the selected starting transmission time.

15. The circuitry according to claim 14 , wherein the probability threshold is predetermined and known to the communications device.

16. The circuitry according to claim 14 , wherein the probability threshold is indicated to the communications device by the infrastructure equipment along with the allocation of the set of radio resources.