Section: 5.14.2.2.1 Sidelink HARQ Entity
Content: For each carrier, there is one Sidelink HARQ Entity at the MAC entity for reception of the SL-SCH, which maintains a number of parallel Sidelink processes. Each Sidelink process is associated with SCI in which the MAC entity is interested. If SCI includes the Group Destination ID, this interest is as determined by the Group Destination ID of the SCI. The Sidelink HARQ Entity directs HARQ information and associated TBs received on the SL-SCH to the corresponding Sidelink processes. The number of Receiving Sidelink processes associated with the Sidelink HARQ Entity is defined in TS 36.331[ Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification ]  [8]. For each subframe of the SL-SCH, the Sidelink HARQ Entity shall: - for each SCI valid in this subframe: - allocate the TB received from the physical layer and the associated HARQ information to a Sidelink process, associate this Sidelink process with this SCI and consider this transmission to be a new transmission. - for each Sidelink process: - if this subframe corresponds to retransmission opportunity for the Sidelink process according to its associated SCI: - allocate the TB received from the physical layer and the associated HARQ information to the Sidelink process and consider this transmission to be a retransmission.