Optimized Scheduling Algorithm for LTE Downlink System

Orthogonal Frequency Division Multiple Access (OFDMA), Multiple Input Multiple Output (MIMO), and Adaptive Modulation and Coding (AMC) are advanced signal processing techniques introduced in the wireless 3GPP LTE standard. In MIMO-OFDMA system, by taking advantage of the spatial dimension and depending on the time-varying wireless channel condition, the most efficient modulation and coding with spatial multiplexing or spatial diversity is selected to increase system capacity or improve system reliability. Wireless resource is divided into resource blocks (RBs), and the central idea is to effectively allocate these RBs to maximize system capacity and satisfy all active users QoS requirements. Scheduling of the available RBs in an optimized manner is therefore a main thrust in the design of LTE system. In this paper, an optimized scheduling algorithm from a holistic view of the LTE downlink system taking into account the combination of frequency-time packet scheduling (FTPS) with added spatial dimension or MIMO and QoS awareness is developed. Simulation results are presented that confirm the performance improvement of the proposed technique.