Performance Evaluation of Superposition Coding in Downlink LTE

In this paper, two issues in assessing the performance of superposition coding (SC) in the downlink Long Term Evolution (LTE) are investigated. The first issue is the prediction of user's signal-to-interference-plus-noise ratio (SINR) at the scheduler based on the user's channel state information (CSI) feedback, when the actual transmission scheme is different from the scheme used for CSI computation. Prediction of the SINR value is needed for the assignment of the modulation order and the code rate. The second issue is with regards to the physical layer abstraction used for modeling the system-level performance of the SC scheme on the basis of the link-level simulation results. With the physical layer abstraction, the complexity of the system level simulation is reduced significantly.