Flow control in the presence of interference cancellation in wireless CDMA networks

We consider the control of uplink packet flow subject to in-cell and out-of-cell interference limitations, in the presence of imperfect Interference Cancellation (IC). The aim is to combine a location-based packet flow control algorithm with multi-user detection for IC. The algorithm assigns packets to be transmitted to separate queues, one for each spatial zone within which packets generate roughly the same in-cell interference and impose equal interference on a neighboring base station. The objective is to maximize data throughput while ensuring fairness among users and limiting queuing and transmission delays. Throughput and fairness are two conflicting objectives that need to be optimized. We show that IC combined with location based scheduling achieves a better tradeoff between throughput and fairness even under stringent resource limitations. Compared to throughput maximization, simulations suggest that maximum fairness can be achieved with a loss in throughput of only 13%, whereas the loss is 65% when IC is not combined with scheduling.