In this paper, we focus on the resource scheduling in the downlink of long term evolution advanced (LTE-A) assuming equal power allocation among subcarriers. Considering the backward compatibility, the LTE-A system serves LTE-A and long term evolution (LTE) users together with carrier aggregation (CA) technology. When CA is applied, a well-designed resource scheduling scheme is essential to the LTE-A system. Joint scheduling (JS) and independent scheduling (INS) are two resource scheduling schemes. JS is optimal in performance but with high complexity. Whereas INS is applied, the LTE users will acquire few resources because they can not support CA technology. And the system fairness is disappointing. In order to improve the system fairness without bringing high complexity to the system, an improved proportional fair (PF) scheduling algorithm base on INS is proposed. In this algorithm, we design a weigh factor which is related with the number of the carriers and the percentage of LTE users. Simulation result shows that the proposed algorithm can effectively enhance the throughput of LTE users and improve the system fairness.
LIN Le-xiangLIU Yuan-anLIU FangXIE GangLIU Kai-mingGE Xin-yang
Network mobility (NEMO) is a protocol proposed for the mobility management of a whole network. It offers seamless Internet connectivity to the mobile end users. However, the NEMO protocol has not been widely used in Internet, because it has not considered the secure problem about authentication and authorization. The proposed framework designed an access control scheme especially used for the NEMO network environment. It is based on the authentication, authorization, and accounting (AAA) system. It can make use of the mobile router to authenticate for all the mobile nodes at the same time, and uses the mobile network node (MNN)-list synchronization mechanism to control the secure access of the MNN. By using the foreign AAA server cache mechanism, this scheme can decrease the authentication time delay and improve the efficiency of the network. The advantages are proved by the comparison with other recent related studies via the OPNETsimulations.