Combined optimal power allocation and adaptive modulation for MIMO systems with imperfect CSI

On the Performance of Link Adaptation Techniques in MIMO Systems

“…The authors would like to thank anonymous reviewers for their valuable comments and for pointing out the similarity of the proposed scheme in Section 3.2 and the one presented in [7]. This work is partly supported by Aalborg University under the Phd Fellowship grant.…”

“…The algorithm for optimal allocation of the modulation order and transmitted power level at each sub-channel is described in (7). Again this optimization solution stems from the useful approximation of BER in (4) and a Lagranger's multiplier procedure.…”

“…With a different approach the authors in [7] proposed a conventional technique which uses normal water filling for the power allocation and applies an adaptive modulation for each sub-channel. In essence, the performance of this scheme and ours is the same.…”

Cross-Layer Combining of Adaptive Modulation and Truncated ARQ in Multichannel Beamforming MIMO Systems

“…Singular value decomposition (SVD) combined with the adaptive modulation and appropriate power allocation enable significant increase of the average spectral efficiency (ASE), in comparison to single-input-single-output (SISO) systems [3][4][5]. However, when all eigenchannels are used the overall error performance of the corresponding system is dominated by the weakest eigenchannel (with the power gain determined with the minimum eigenvalue of the corresponding Wishart matrix) [5].…”

Link adaptation as a technique to achieve information-theoretic limits in MIMO systems?

“…it is imperative to achieve the channel capacity [8,9]. In several previous papers it is recognized that adaptive modulation represents necessary part of the transmission system, and the impact of imperfect CSI is described in details in [10,11,12].…”