Channel assignment in dual cellular systems

In this paper the traffic performance for different channel assignment methods for analog cellular systems in a transition to a Digital Cellular Systems, Dual System, is studied. As actually conceived, Dual Cellular Systems have two types of subscribers; Analog and Dual subscribers. Analog subscribers can only access analog channels while Dual subscribers first size a digital channel, and then, if there are not available digital channels, the subscribers would try to occupy an analog channel. In order to evaluate the blocking probabilities for this scheme, two main methods have been followed. One ruling on an equivalent random approach (Wilkinson Method) and, on the other hand, a simulation based approach was also followed. Different scenarios, in terms of diverse analog to digital subscriber proportion as well as different loads and channel assignment practices were studied. The present results suggest a limit on the proportion of subscribers for different conditions. Alternative simple channel assignment methods that allows to improve operation limits are also reported. These methods were also simulated.