METHODS OF RETRANSMISSION IN SEMI-PERSISTENT SCHEDULING WITHOUT EXPLICIT HARQ FEEDBACK

Example techniques for data retransmission in systems that do not utilize explicit hybrid automatic repeat request (HARQ) feedback are presented, including an example method by a wireless device that includes starting a timer for a hybrid automatic repeat request (HARQ) process associated with a transport block (TB) transmission by the wireless device to the network node. The method includes identifying a HARQ policy for the HARQ process, the HARQ policy governing whether the wireless device is to retransmit the TB or transmit a new TB where no HARQ feedback responsive to the TB transmission is received from the network node before the timer expires. Furthermore, the method includes retransmitting the TB or transmitting the new TB according to the HARQ policy at a next periodic transmission occasion for the HARQ process after the timer expires. Methods at a network node and related apparatuses and computer programs are also presented.