Mathematical problems in the development of a cordless PABX

Estimating the performance of a cordless PABX leads to three main modelling problems. Such systems are usually installed in buildings, so the behaviour of radio waves in this environment must be modelled. Cordless telephone users can move cordless telephones between locations, causing the traffic in various parts of the system to vary with time. Finally, the quantity of equipment provided is limited, so there is the usual congestion. The author describes models for radio coverage, user movement and congestion, including some estimates of the numbers of cordless telephones that can be supported by cordless PABXs