UU INTERFACE ENHANCEMENT FOR NR V2X
A method and apparatus for performing sidelink communications in a wireless transmit receive unit (WTRU) using Long Term Evolution (LTE) and New Radio (NR) technologies is described herein. A WTRU receives downlink control information (DCI) on a physical downlink control channel (PDCCH) from a gNodeB (gNB), wherein the DCI is associated with a cyclic redundancy check (CRC). The a determination is made as to whether the DCI is for an LTE or NR technology sidelink transmission. On a condition that the DCI is for NR technology, the WTRU determines which transmit modulation and coding scheme (MCS) table to apply based on the masking of at least some of the bits in the CRC. Then the WTRU transmits sidelink data on resources indicated by the DCI using the determined MCS table. The WTRU may also receive HARQ feedback on resources indicated by the DCI for HARQ feedback.
1 . A wireless transmit receive unit (WTRU) configured to perform for sidelink communications using Long Term Evolution (LTE) and New Radio (NR) technologies, the WTRU comprising:
a receiver configured to receive a downlink control information (DCI) on a physical downlink control channel (PDCCH) from a gNodeB (gNB), wherein the DCI is associated with a cyclic redundancy check (CRC);
a processor configured to determine whether the DCI is for an LTE or NR technology sidelink transmission;
the processor is further configured to, on a condition that the DCI is for NR technology, determine a transmit modulation and coding scheme (MCS) table to apply based on the masking of at least some of the bits in the CRC;
a transmitter configured to transmit sidelink data on resources indicated by the DCI using the determined MCS table.
2 . The WTRU of claim 1 wherein the receiver is further configured to receive HARQ feedback on resources indicated by the DCI for HARQ feedback.
3 . The WTRU of claim 1 wherein the processor is configured to determine to apply MCS table 1 if the RNTI mask is on the last 16 CRC bits.
4 . The WTRU of claim 1 wherein the processor is configured to determine to apply MCS table 3 if the RNTI mask is on the next to last 16 CRC bits.
5 . The WTRU of claim 1 wherein the processor is further configured to, on a condition that the DCI is for LTE technology, transmit sidelink data on resources indicated by the DCI.
6 . The WTRU of claim 1 wherein the DCI includes and an explicit indication of whether a transmission grant is for LTE sidelink or for NR sidelink.
7 . The WTRU of claim 1 wherein the processor is further configured to monitor sidelink transmissions based on whether an operational frequency is contained in an inter-frequency information list or in an inter-radio access technology (inter-RAT) information list.
8 . The WTRU of claim 1 wherein transmitter is further configured to transmit sidelink communications based on whether an operational frequency is contained in an inter-frequency information list or in an inter-radio access technology (inter-RAT) information list, and where the WTRU is in radio resource control (RRC) connected mode, RRC idle mode or RRC inactive mode.
9 . The WTRU of claim 1 wherein the processor is configured to send a buffer status report with indication of unicast, groupcast sidelink transmissions, wherein the buffer status report triggers the gNB to send the DCI.
10 . The WTRU of claim 9 wherein the DCI includes a sidelink transmission grant for both data transmissions and HARQ feedback transmissions.
11 . A method performed by a wireless transmit receive unit (WTRU) configured to perform for sidelink communications using Long Term Evolution (LTE) and New Radio (NR) technologies, the method comprising:
receiving a downlink control information (DCI) on a physical downlink control channel (PDCCH) from a gNodeB (gNB), wherein the DCI is associated with a cyclic redundancy check (CRC);
determining whether the DCI is for an LTE or NR technology sidelink transmission;
on a condition that the DCI is for NR technology, determining a transmit modulation and coding scheme (MCS) table to apply based on the masking of at least some of the bits in the CRC;
transmitting sidelink data on resources indicated by the DCI using the determined MCS table.
12 . The method of claim 11 further comprising: receiving HARQ feedback on resources indicated by the DCI for HARQ feedback.
13 . The method of claim 11 further comprising determining to apply an MCS table 1 if the RNTI mask is on the last 16 CRC bits.
14 . The method of claim 11 further comprising: determining whether to apply MCS table 3 on a condition that an radio network temporary identifier (RNTI) mask is on the next to last 16 CRC bits.
15 . The method of claim 11 further comprising: on a condition that the DCI is for LTE technology, transmitting sidelink data on resources indicated by the DCI.
16 . The method of claim 11 wherein the DCI includes and an explicit indication of whether the transmission grant is for LTE sidelink or for NR sidelink.
17 . The method of claim 11 further comprising: monitoring sidelink transmissions based on whether an operational frequency is contained in an inter-frequency information list or in an inter-radio access technology (inter-RAT) information list.
18 . The method of claim 11 further comprising: transmitting sidelink communications based on whether an operational frequency is contained in an inter-frequency information list or in an inter-radio access technology (inter-RAT) information list, and where the WTRU is in radio resource control (RRC) connected mode, RRC idle mode or RRC inactive mode.
19 . The method of claim 11 further comprising: sending a buffer status report with indication of unicast, groupcast sidelink transmissions, wherein the buffer status report triggers the gNB to send the DCI.
20 . The method of claim 19 wherein the DCI includes a sidelink transmission grant for both data transmissions and HARQ feedback transmissions.