Transmit diversity for sidelink communications in unlicensed spectrum

An apparatus for wireless communications at a user equipment (UE), comprising:

• one or more processors;
• one or more memories coupled with the one or more processors;
• and
• instructions stored in the one or more memories and executable by the one or more processors to cause the apparatus to:
• receive a control message indicating a transmit diversity configuration that indicates a plurality of component carriers available for sidelink communication within a shared radio frequency spectrum band that indicates to transmit a first redundancy version of a transport block via a first component carrier of the plurality of component carriers and to transmit a second redundancy version of the transport block via a second component carrier of the plurality of component carriers;
• and
• transmit, based at least in part on the transmit diversity configuration, a first sidelink message having the first redundancy version of the transport block via the first component carrier of the plurality of component carriers and a second sidelink message having the second redundancy version of the transport block via the second component carrier of the plurality of component carriers within the shared radio frequency spectrum band.

An apparatus for wireless communications at a user equipment (UE), comprising:

• one or more processors;
• one or more memories coupled with the one or more processors;
• and
• instructions stored in the one or more memories and executable by the one or more processors to cause the apparatus to:
• identify a transmit diversity configuration that indicates a plurality of component carriers available for sidelink communications within a shared radio frequency spectrum band and a plurality of precoding matrices;
• and
• transmit, based at least in part on the transmit diversity configuration, a first sidelink message comprising a transport block precoded using a first precoding matrix of the plurality of precoding matrices and a second sidelink message comprising the transport block precoded using a second precoding matrix of the plurality of precoding matrices on a first component carrier and a second component carrier of the plurality of component carriers within the shared radio frequency spectrum band.