Using cross-system diversity in heterogeneous networks : throughput optimization

This paper investigates the situation where a group of terminals can be simultaneously connected to several base stations, using distinct technologies on non-overlapping frequency bands. We introduce and solve the problem of optimal power allocation (in the sense of the ergodic sum-rate), for terminals in the uplink, using three types of receiver: the optimum receiver, minimum mean square error and matched filters. Key results from random matrix theory allow us to solve the corresponding optimization problems. Simulations validate our approach, and illustrate the performance gain obtained by using several technologies simultaneously, instead of one at a time.