A comprehensive and practical model for HARQ in LTE system

This paper presents a HARQ model in LTE system level simulation capable of reliably predicting the block error ratio improvement. Our model is based on the Mutual Information Effective SINR Mapping (MIESM) which is usually used as the link-to-System (L2S) interface and both SISO and MIMO transmission mode are supported. In addition, taking the rate matching, soft combining into account, the model distinguishes between Chase Combining (CC) gains and Incremental Redundancy (IR) gains from retransmission packets. As a consequence, our model can not only avoid bit level operations so that to be used in system level simulation but also achieve good accuracy. The simulation results show that HARQ can reduce the block error rate (BLER), improve throughput, and perform better in low-speed scenario than in high-speed case.