Throughput Analysis of Proportional Fair Scheduling for Sparse and Ultra-Dense Interference-Limited OFDMA/LTE Networks

Various system tasks, such as interference coordination, handover decisions, admission control, and so on in current cellular networks require precise mid-term (spanning over a few seconds) performance models. Due to channel-dependent scheduling at the base station, these performance models are not simple to obtain. Furthermore, LTE cellular systems are interference limited; hence, the way interference is modeled is crucial for the accuracy. In this paper, we present a closed-form analytical model for the throughput expectation of proportional fair scheduling in orthogonal frequency division multiple access/LTE networks. The model takes into account a precise signal-to-interference-and-noise ratio (SINR) distribution as well as considering limitations with respect to modulation and coding, as encountered in LTE networks. Furthermore, the analysis is extended to ultra-dense deployments likely to happen in the 5th generation of cellular networks. The resulting analytical performance model is validated by means of simulations, considering realistic network deployments. Compared with related work, the model introduced in this paper demonstrates a significantly higher accuracy for mid-term throughput estimation.