(A) time slot allocation algorithm for capacity maximization in CDMA/TDD system

Abstract

Recently, the mobile communications system is expected to provide various wireless multimedia services. Since multimedia services generally need more downlink traffic than uplink traffic, the current CDMA/FDD system can not utilize resources efficiently. CDMA/TDD system is proposed to solve this problem. In CDMA/TDD system, inter-cell interference occurs when time slot is allocated differently in neighbor cells. In this thesis, we propose a time slot allocation algorithm for capacity maximization considering the inter-cell interference. The proposed algorithm is based on LP relaxation method. By solving LP relaxed sub-problem, we can obtain a good solution in a short time. By calculating the total system capacity according to uplink and downlink asymmetry of a cell, we show that the proposed algorithm provides more system capacity than SA strategy in case that traffic asymmetry level is intensive.