Group scheduling in advanced cellular systems using directional antennas
Long Term Evolution has been the most popular technique all around the world, and Multi-User Multiple Input Multiple Output is widely considered a key technology for system capacity improvement in modern wireless networks. At the same time how to improve throughput maximization and user's fairness in the network is becoming an advanced issue. Beamforming technology and group scheduling have provided a new method to address this issue. This work provides the trade-off between efficiency and fairness using group scheduling, including the Maximum Carrier to Interference, Round Robin and Proportional Fairness scheduling schemes, under the consideration of the fairness of each group in the wireless networks. This is vitally important for increasing both the total and individual group's throughput. Beamforming technology is used to increase the throughput at the direct angle area where the beam focuses. This is especially helpful for the mobile users at the edge of the network cell, who will usually have the worst channel conditions. Beamforming will increase the Signal-to-Noise Ratio by 5dB as designed. Also, the beam will switch its angle with some certain feedback algorithms, such as those based on the decreasing of the possible Signal-to-Noise Ratio compared with its previous time slot, the maximum and minimum difference of possible and location Signal-to-Noise Ratio, using the throughput measurement in the algorithms respectively. These schemes will boost the signal strength and also lead to increased total throughput, but at the same time they will face fairness requirements between the groups. From simulation result, it is shown that with every beamforming type, the throughput will have certain increases. While at the same time the fairness has been improved. Some new approaches have addressed the guarantee of the minimum throughput for every group. Moreover, with the adjustment of the key parameters our simulation is more close to the real wireless networks, which expresses a future view of the wireless networks.
Table of Contents
Introduction -- Background details -- Simulation design -- Simulation results and analysis -- Conclusion and future scope