Efficient Technique to Reduce the Retransmission Latency of Packets from RLC layer in Carrier Aggregated 5G RAN

Typically in wireless communication systems, reliable data transfer is one of the key factors considered. Re-transmission is the one of the most common method defined from Physical layer to Transport layer for achieving reliability. In most scenarios, retransmission happens when the receiver peer entity sends its feedback through ACK/NACK to the transmitter peer entity. Although this mechanism of waiting for the feedback brings reliability, it will also increase the latency of the packets to be retransmitted. This would potentially affect the overall performance of the system. In this paper, a 5G system that is configured and activated with Carrier Aggregation (CA) is considered. We propose a mechanism which reduces the overall retransmission latency involved during the higher layer packet retransmissions on account of transmission failures at lower layer. It initiates a quick-retransmission over different serving cell(s) via lower layer itself. We evaluate the improvements in the latency by adopting the novel techniques discussed in this paper. Simulation results show that around 95% in reduction of latency can be achieved in retransmission of Radio Link Layer (RLC) packets.