Study of Robust Adaptive Power allocation for the Downlink of Multiple-Antenna Systems

TL;DR

This paper proposes two adaptive power allocation algorithms for MIMO downlink systems that are more robust to imperfect channel information, improving sum-rate performance over traditional methods.

Contribution

The paper introduces novel adaptive power allocation algorithms that specifically address the challenge of imperfect CSIT in MIMO systems, enhancing robustness and performance.

Findings

Proposed algorithms outperform conventional methods in sum-rate.

Algorithms demonstrate robustness against CSIT imperfections.

Simulation results confirm improved system throughput.

Abstract

Multiple-input multiple-output (MIMO) systems greatly increase the overall throughput of wireless systems since they are capable of transmitting multiple streams employing the same time-frequency resources. However, this gain requires an appropriate precoder design and a power allocation technique. In general, precoders and power allocation schemes are designed assuming perfect channel estate information (CSI). Nonetheless, this is an optimistic assumption since real systems only possess partial or imperfect CSI at the transmitter (CSIT). The imperfect CSIT originates residual inter-user interference, which is detrimental for wireless systems. In this paper, two adaptive power allocation algorithms are proposed, which are more robust against CSIT imperfections than conventional techniques. Both techniques employ the mean square error as the objective function. Simulation results show that the proposed techniques obtain a higher performance in terms of sum-rate than conventional approaches.