Adjustable subcarrier allocation for spectral efficiency and user fairness in 3GPP LTE downlink systems

In this paper, adjustable subcarrier allocation algorithm is proposed for both system spectral efficiency and user-throughput fairness (or throughput requirement). There exists trade-off between two performance metrics. The proposed subcarrier allocation method can easily coordinate system performance between spectral efficiency and user-throughput fairness. To achieve adjustable goal, we define cost function combined by adjustable weightings to the terms of both spectral efficiency and user- throughput fairness. Based on 3GPP LTE downlink system model simulations, we can show that spectral efficiency mode in the proposed algorithm can achieve much lower outage probability than Wong's algorithm, which emphasizes spectral efficiency, with similar total spectral efficiency and throughput fairness. Also the user requirement-emphasized mode in the proposed one can achieve better performance than You's algorithm, which emphasizes user data rate requirements, in terms of spectral efficiency, outage probability, and fairness pattern.