Section: 5.15.2.1.1 Sidelink HARQ Entity
Content: There is one Sidelink HARQ Entity at the MAC entity for reception on the SL-DCH which maintains a number of parallel Sidelink processes. The Sidelink HARQ Entity directs HARQ information and associated TBs received on the SL-DCH to the corresponding Sidelink processes. The number of receiving Sidelink processes per Sidelink HARQ Entity is specified in TS 36.331[ Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification ]  [8]. For each subframe of the SL-DCH, the Sidelink HARQ Entity shall: - receive the TB and the associated HARQ information from the physical layer; - if this subframe corresponds to a new transmission opportunity: - allocate the received TB (if any) and the associated HARQ information to a non-running Sidelink process and consider this transmission to be a new transmission. - else, if this subframe corresponds to a retransmission opportunity: - allocate the received TB (if any) and the associated HARQ information to its Sidelink process and consider this transmission to be a retransmission.