Analog-to-digital transition: selecting the optimal cellular radio mix

The capacity gains from the transition from analog-to-digital time-division multiple-access (TDMA) air-interface technology depend on the number of base-station radios (transceivers) changed from analog to digital. It is possible to have no capacity gains, and even losses, if too many radios are changed over. This paper addresses the problem of finding the optimal radio mix. An analytical model is developed to compute the blocking rate experienced by subscribers in a cell, given the cell's offered load, the mix of analog and dual-mode subscriber units, and the analog-to-digital split of the radio frequency (RF) channels available to the cell.