Cross-layer resource allocation and scheduling in LTE systems under imperfect CSIT

3GPP LTE/LTE-A is set to become the dominant technology for 4G and Beyond 4G wireless communications. As in any MIMO-OFDMA-based system, scheduling and resource allocation algorithms play a pivotal role towards the maximisation of capacity while providing support to applications with heterogeneous QoS requirements. To this end, the transmitter is assumed to have access to channel state information (CSIT) that, in most practical situations, will not be perfect. This paper first presents an analytical framework for QoS-guaranteed cross-layer scheduling and resource allocation that takes into account the accuracy of the available CSIT and then particularizes using specifications drawn from the LTE/LTE-A standards. Simulation results are shown assessing the performance of different schedulers and power allocation policies and the impact CSIT accuracy has on them.