MIMO Pre-processing schemes and their robustness to channel estimation errors
Authors
Ortolan, François ; Bouquet, Philippe
Term
10. term
Publication year
2008
Pages
91
Abstract
I trådløse systemer med flere antenner (MIMO) forbereder man signaler før udsendelse for at øge pålidelighed og datahastighed. Dette projekt undersøger, hvordan ufuldkommen kanalestimering påvirker effektiviteten af tre forbehandlingsmetoder: eigenmode-transmission (at sende langs kanalens stærkeste tilstande), water-filling (at fordele sendeeffekt mellem kanaler) og adaptiv modulering og kodning (at tilpasse signalet til forholdene). Kanalestimering, også kaldet Channel State Information (CSI), kan forringes af støj og Doppler-effekter, når sender eller modtager bevæger sig. Ved hjælp af matematiske modeller og computersimuleringer analyserer vi betydningen af støj og tidsvarierende CSI for MIMO. Resultaterne viser, at nøjagtig kanalestimering er afgørende: ufuldkommen CSI mindsker udbyttet af disse forbehandlingsmetoder i multiantenne-systemer.
In multi-antenna (MIMO) wireless systems, pre-processing prepares signals before transmission to improve reliability and data rate. This project studies how imperfect channel estimation affects the efficiency of three pre-processing techniques: eigenmode transmission (sending along the channel’s strongest modes), water-filling (allocating power across channels), and adaptive modulation and coding (adjusting the signal to conditions). Channel estimation, also called Channel State Information (CSI), can be degraded by noise and Doppler effects when the transmitter or receiver moves. Using mathematical models and computer simulations, we analyze the impact of noisy and time-varying CSI on MIMO performance. The results show that accurate channel estimation is crucial: imperfections in CSI reduce the benefits of these pre-processing methods in multi-antenna systems.
[This abstract was generated with the help of AI]
Keywords
MIMO ; Pre-Processing ; Processing ; CSI ; CSI imperfection ; AMC ; Water-filling ; Waterfilling ; Eigenmode ; Eigen-mode