HARQ Process Mapping Mechanism in LTE-Advanced System with Carrier Aggregation ⋆

This paper analyzes the static mapping and flexible mapping mechanism of HARQ process with carrier aggregation, and then improves the flexible mapping of HARQ process which not only can guarantee the improvement of system performance but also is able to reduce the retransmission times to the highest extent. Such improved scheme realizes the performance gains by taking the historical channel quality information into consideration and adding 1 bit for indication. It proves favorable by analyzing and simulating the performance factors such as mapping mechanisms, retransmission number, block error rate, and throughput and so on under different weight factors.