Hybrid automatic repeat request for uplink ultra-reliable and low-latency communications

A base station apparatus comprising:

• transmitting circuitry configured to transmit a radio resource control message including first information used for configuring a number of repetitions and a periodicity, the number of the repetitions being for transmissions of a transport block (TB),
• the transmitting circuitry configured to transmit a radio resource control message including second information used for configuring a monitoring occasion for a symbol,
• the transmitting circuitry configured to transmit a first physical downlink control channel (PDCCH) with cyclic redundancy check (CRC) scrambled by a cell radio network temporary identifier (C-RNTI),
• the transmitting circuitry configured to transmit a second PDCCH with CRC scrambled by a second RNTI different from the C-RNTI;
• and
• receiving circuitry configured to receive on a physical uplink shared channel (PUSCH), based on the first information, transmissions of the TB, wherein
• in a case that the PDCCH with CRC scrambled by the C-RNTI is transmitted, the receiving circuitry is configured to receive a transmission on the PUSCH scheduled by using the PDCCH with CRC scrambled by the C-RNTI,
• in a case that the PDCCH with CRC scrambled by the second RNTI is transmitted, the receiving circuitry is configured to receive a retransmission of the TB on the PUSCH scheduled by using the PDCCH with CRC scrambled by the second RNTI, and
• the second PDCCH with CRC scrambled by the second RNTI is transmitted, based on second information, in a user equipment-specific search space given by the second RNTI.

A communication method of a user equipment comprising:

• receiving a radio resource control message including first information used for configuring a number of repetitions and a periodicity, the number of the repetitions being for transmissions of a transport block (TB);
• receiving a radio resource control message including second information used for configuring a monitoring occasion for a symbol;
• monitoring a first physical downlink control channel (PDCCH) with cyclic redundancy check (CRC) scrambled by a cell radio network temporary identifier (C-RNTI);
• monitoring a second PDCCH with CRC scrambled by a second RNTI different from the C-RNTI;
• and
• performing on a physical uplink shared channel (PUSCH), based on the first information, transmissions of the TB, wherein
• in a case that the PDCCH with CRC scrambled by the C-RNTI is received, performing a transmission on the PUSCH scheduled by using the PDCCH with CRC scrambled by the C-RNTI,
• in a case that the PDCCH with CRC scrambled by the second RNTI is received, performing a retransmission of the TB on the PUSCH scheduled by using the PDCCH with CRC scrambled by the second RNTI, and
• the second PDCCH with CRC scrambled by the second RNTI is monitored, based on second information, in a user equipment-specific search space given by the second RNTI.

A communication method of a base station apparatus comprising:

• transmitting a radio resource control message including first information used for configuring a number of repetitions and a periodicity, the number of the repetitions being for transmissions of a transport block (TB);
• transmitting a radio resource control message including second information used for configuring a monitoring occasion for a symbol;
• transmitting a first physical downlink control channel (PDCCH) with cyclic redundancy check (CRC) scrambled by a cell radio network temporary identifier (C-RNTI);
• transmitting a second PDCCH with CRC scrambled by a second RNTI different from the C-RNTI;
• and
• receiving on a physical uplink shared channel (PUSCH), based on the first information, transmissions of the TB, wherein
• in a case that the PDCCH with CRC scrambled by the C-RNTI is transmitted, receiving a transmission on the PUSCH scheduled by using the PDCCH with CRC scrambled by the C-RNTI,
• in a case that the PDCCH with CRC scrambled by the second RNTI is transmitted, receiving a retransmission of the TB on the PUSCH scheduled by using the PDCCH with CRC scrambled by the second RNTI, and
• the second PDCCH with CRC scrambled by the second RNTI is transmitted, based on second information, in a user equipment-specific search space given by the second RNTI.