TABLE OF CONTENTS In this chapter, we analyze the Erlang capacity of a CDMA system supporting voice and delay-tolerant data services and consider the characteristics of delay-tolerant traffic, known as the delay confidence. Delay confidence is defined as the probability that a new data call is accepted within the maximum tolerable delay without being blocked. In this case, the Erlang capacity is confined not only by the required blocking probability of voice call but also by the required delay confidence of data call. For the performance analysis, we develop a two-dimensional Markov chain model, based on the first-come-first-served (FCFS) service discipline, and present a numerical procedure to analyze the Erlang capacity. As a result, it is necessary to create a balance between the Erlang capacity with respect to the blocking probability of voice calls and one with respect to the delay confidence of data calls, in order to accommodate more Erlang capacity. In this chapter, we demonstrate the balance by properly selecting the size of the designated queue for data traffic.
The objective of future wireless communication systems is to provide users with multimedia services (e.g., voice, interactive data, file transfer, Internet access, and images) comparable to those provided by the wired communication systems.
Different traffic types may have different QoS requirements, which makes the capacity evaluation more complex. Many efforts have been made to analyze the capacity of a CDMA system. Typically, the capacity of a CDMA system has been defined as the maximum...
