In this paper, we first describe the architecture of base station (BS) in the CDMA mobile system (CMS) and then model one base station controller group (BSCG) as a queuing network. By using an analytic method for the given queuing network model, we evaluate the mean waiting time at each transmission node in the packet networks between traffic channel element (TCE) in the base station transceiver subsystem (BTS) and selector in the base station controller (BSC). As the transmission technology for the traffic data from TCE to BSC during the call conversation time, we consider two kinds of transmission schemes such as the frame non-staggering scheme and the frame staggering scheme. Then, we evaluate the delay time of traffic data from the TCE to the selector and the quality degradation probability by simulation. Based on these results, we present the call handling capacity of one BSC group for mobile originated calls in the CMS(CDMA Mobile System).