CDPD performance: a joint analysis of the physical and MAC layers

The Cellular Digital Packet Data (CDPD) system is the first public wireless data ever deployed in the US. As its traffic continues to grow, potential new customers require to know the platform´s quality-of-service (QoS) performance data prior to subscribing to the service. Consequently, network planners are searching for a simple model which can provide QoS analysis “instantly”, rather than conducting long (and costly) simulations. This paper provides such model. CDPD uses a random-access MAC layer protocol known as the DSMA/CD, to control the users packet transmission on the reverse link. In general, the success of the transmitted packets, as well as the delay incurred, depends heavily on both: the efficiency with which the DSMA/CD controls packet collisions, and the degree of error-free reception provided by the physical layer. Therefore, one must consider the joint operation of the two in order to produce quotable realistic traffic performance figures. This paper focuses on the joint operation of the two named layers