Analysis of Practical Frequency Selective Scheduling Algorithms in LTE Networks

The use of orthogonal frequency division multiple access (OFDMA) in Long Term Evolution (LTE) and LTE- Advanced systems facilitates the potential for scheduling cell users on orthogonal time-frequency resource blocks selectively. This paper identifies several frequency selective scheduling (FSS) algorithms and studies their performance and optimality under certain identified constraints in practice. The performance is studied under the limiting factors of cell load, user mobility, the number of users per cell, data traffic characteristics, and the LTE standards constraint of using a single modulation and coding scheme (MCS) across assigned resource blocks. To address the single MCS restriction, a dynamic Proportional Fair (PF) scheduling algorithm is developed to achieve optimal allocation under this constraint. The gain either in signal-to-interference-plus-noise ratio (SINR) or cell throughput achieved from these algorithms is statistically quantified using detailed LTE system level simulations.