Sidelink HARQ Feedback Timing Validation

The UE performs preliminary validation of the timing value upon receiving DCI, determining before transmission whether the value is applicable. This preliminary check prevents wasteful transmissions and allows the UE to buffer feedback appropriately until a valid transmission opportunity arises, thereby resolving the contradiction between avoiding resource wastage and managing feedback complexity.

The UE dynamically adjusts its feedback transmission strategy based on the validity of the received timing value. When the timing value is inapplicable, the UE buffers the feedback; when a valid timing value is received (either originally or via DCI retransmission), the UE transmits immediately. This dynamic approach optimizes resource utilization while minimizing unnecessary delays.

The system implements a feedback mechanism where the UE reports the applicability of received timing values to the network. This feedback loop enables the network to understand when feedback transmissions are delayed due to inapplicable timing values, allowing for coordinated resource allocation and maintaining communication reliability while managing transmission efficiency.

The UE changes the state parameter of the timing value from undefined to validated by performing a validity check against predefined criteria (e.g., whether the value corresponds to a future slot). This parameter transformation ensures transmission accuracy while maintaining relatively simple processing logic based on standardized validation rules.