System and method embodiments are provided for enabling flexible and reliable UE-to-UE based relay. The embodiments include using fountain codes for combining signals at a suitable network layer higher than a media access control (MAC) sub-layer and using a MAC sub-layer hybrid automatic repeat request (HARQ) transmission scheme. When a relay UE in a UE group for joint reception receives, from a network access point, a data packet intended for a destination UE in the UE group and including fountain code at the higher network layer, the relay UE sends the data packet to the destination UE and returns a HARQ ACK message at the MAC sub-layer to the access point. The destination UE then receives and decodes the data packet. Subsequently, upon receiving the entire data, the destination UE sends an ACK message at the higher network layer to the access point.