A QoS-Aware Interference Balancing Scheme for Multiuser MIMO Systems

In multiuser MIMO systems, the achievable system data rate as well as quality of service (QoS) of individual users is limited by the inter-user interference (IUI). The interference balancing issue via power allocation can be usually formulated as a nonconvex optimization problem which will become more intractable with nonconvex QoS constraints. In this paper we focus on the challenging QoS-aware optimal power allocation problem, aiming to maximize the system sum rate and guarantee the users\´ minimum data rates. As a result, a "Polynomial Approximations based on Single Condensation" (PASC) strategy is proposed which transforms the underlying problem to a series of tractable Geometric Programming (GP) problems through single condensation scheme. Extensive simulations have been conducted and the results indicate that PASC is quite suitable to tackle the problem, which can achieve a good balance between the system sum rate and the individual QoS requirements.