A study on the effective interconnection method between base stations and selector bank subsystem in CDMA cellular networks

Abstract

A CDMA cellular land network (CCLN) consists of base stations connected to a selector bank subsystem. In the case of considering only the voice traffic, CCLN can be designed based on E1/T1 physical line and HDLC protocol with fixed or variable length. However, it is necessary to support not only voice but also data traffic in the CDMA cellular system. Thus, it is necessary to use physical lines efficiently to increase bandwidth efficiency and transmission speed. However, the conventional CCLN has some problems in that the bandwidth is wasted because each BTS has its own private line. In this paper, a method using DQDB MAN as a CDMA interconnect subsystem (CIS) is considered, and the performances of the conventional and proposed method are analyzed by computer simulation. According to the simulation results, if the traffic from all mobile stations is uniformly distributed among all BTS's, the performances of both the conventional and proposed methodologies turn out to be almost equal. However, the performance of the methodology using the DQDB MAN is much better than that of the conventional method, in the case that the traffic from all mobile stations is nonuniformly distributed.