HARQ Strategies for Relay Systems with Limited Feedback

Hybrid automatic repeat request (HARQ) techniques based on rate compatible error correction codes (ECC) have been extensively studied to maximize the achievable data rate while maintaining error correction performance. However, previous works have focused on single-hop transmissions of a single codeword, whereas in practical situations, a direct link between source and destination is not always available and codewords are often bundled into packets. This research will propose HARQ techniques suitable for multi-hop relay systems with codeword bundling and limited feedback capabilities. It will analyze the trade-offs when choosing the type and amount of incremental redundancy (IR) as well as different relay strategies.