Resource planning for wireless PBX systems

The wireless private branch exchange (PBX) system is considered as a wireless extension to enterprise networking. In a WPBX, several base stations are connected to the PBX, and the PBX is then connected to the public switched telephone network (PSTN). Since only a small number of lines are expected to be busy at the same time, the capacity (number of the external lines) between the PBX and the PSTN is typically smaller than the sum of the capacities (radio channels) of the individual base stations. It is important to determine the capacity of the WPBX to optimize the performance of the system. This paper proposes an analytic model for WPBX resource planning. Based on the workload to the WPBX, our model provides the guidelines to determine the capacities of the PBX and the base stations.