Interference avoidance versus iterative water filling in multiaccess vector channels

We present an analysis of the relationship between the application of greedy interference avoidance and that of iterative water filling for vector multiaccess channels. The two methods converge to fixed points with similar properties corresponding to maximum sum capacity. However, the former is used for optimizing CDMA codewords, whereas the latter is used for optimizing transmit covariance matrices. We present numerical results from simulations and make a parallel between the two procedures, discussing differences and similarities.