Hierarchical SIR and rate control for CDMA data users on the forward link

We consider SIR and rate control algorithms for data users on the CDMA forward link under constraints on delay (i.e., limited allowable retransmissions), data error rate and total power. The QoS for data users is mapped onto a family of utility functions that reflect the tradeoff between total system throughput and fairness (similarity in data rates of users). The proposed algorithm uses an hierarchical control structure that is simple to implement in a distributed manner. Specifically, the data rates are adjusted jointly by the base station while the SIR targets are adjusted by the mobiles using information specific to the individual users.