Erlang Capacity of a CDMA Link with Transmission Rate Control

Regulating the transmission rate of non real-time applications offers enhanced flexibility for QoS management and capacity control on a CDMA link. For a system working at saturation conditions, i.e., with the highest number of on-going transmissions, controlling data rates can further enhance its capacity. A more thorough investigation of this possibility and the trade-offs involved is presented in this paper. By an analytic modeling, the Erlang capacity of a CDMA link is studied when modifying the physical transmission rates on the link. The analysis is extended to an asymptotic scaling regime. It is shown that the most efficient way of boosting this capacity is by lowering transmission rates, which nevertheless comes at the expense of increased transfer delays and energy consumption.