A Concept for Efficient System-Level Simulations of OFDMA Systems with Proportional Fair Fast Scheduling

System-level simulations of packet-based orthogonal frequency-division multiple access (OFDMA) cellular networks require a proper consideration of the channel-dependent fast fading/scheduling in order to produce meaningful results. However, generating the time and frequency selective fast fading channels and performing detailed channel-adaptive scheduling for each user in a multi-cellular system is computationally too expensive in most system-level simulations. To this end, we propose an efficient mapping technique that allows to accurately characterize the performance of the fast-scheduling system using two parameters: the average effective post-scheduling SINR gain and the ratio of allocated resources, both conditioned on the SINR and the velocity of a user in a scenario defined by the number of co-scheduled users. To derive these parameters for different numbers of users at different velocities and SINR levels, we perform detailed link level simulations including fast scheduling for the downlink of a long term evolution (LTE) system.