Modeling RF impact on TCP/RLP in IS-95B

One of the first commercial deployments of high-speed cellular data service is offered by carriers deploying the IS-95B system. As an enhancement of the IS-95A CDMA system, the B version provides approximately 64 kbit/s raw data rate to mobile users over the radio link protocol (RLP). Frame erasure rate (FER) is the main radio link parameter used in the studies of TCP over RLP. Previous studies have mostly assumed that forward link power control in IS-95A does not correct frame erasures due to fast fading. The forward link power control in the IS-95B system offers faster feedback to the infrastructure that we try to model. We propose a simple FER model that captures the erasure patterns more accurately in the IS-95B system. We use this model to study long-term average TCP throughput in IS-95B. From the model it appears that the power control in IS-95B, while reducing the interference compared to IS-95A, does not have a negative impact on end-to-end performance of a single TCP connection. We also confirm some of the earlier findings and illustrate new ones specific to IS-95B