Call Admission Control Scheme Adapted to Foreign Cell Environment in Direct Spread Code Division Multiple Access Cellular System

摘要

The present invention relates to a call admission control method in a DS-CDMA cellular system.;The radio link capacity of the base station of the DS-CDMA cellular system is limited by the reverse link capacity. The capacity of the reverse link is determined by the amount of interference received from the neighbor cell and is closely related to the traffic load of the neighbor cell. When allocating a new call, the base station should ensure that the total number of users does not exceed the reverse link capacity. If the base station allocates a call exceeding the reverse link capacity, the mobile station in the cell boundary may be forcibly interrupted depending on the radio environment. .;Therefore, in the present invention, the average and the variance of the outer cell interference amount are estimated from the received signal strength and the total received interference amount used for the closed loop power control of the base station, and the base station calculates the reverse link capacity using the average and the variance of the estimated outer cell interference amount. Accordingly, a call admission control method adapted to an external cell environment in a DS-CDMA cellular system that can improve frequency usage efficiency and reduce call interruption probability is proposed.