English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Holographic MIMO (hMIMO) systems with a massive number of individuallycontrolled antennas N make minimum mean square error (MMSE) channel estimationparticularly challenging, due to its computational complexity that scales as$N^3$ . This paper investigates uniform linear arrays and proposes alow-complexity method based on the discrete Fourier transform (DFT)approximation, which follows from replacing the covariance matrix by a suitablecirculant matrix. Numerical results show that, already for arrays with moderatesize (in the order of tens of wavelengths), it achieves the same performance ofthe optimal MMSE, but with a significant lower computational load that scalesas $N \log N$. Interestingly, the proposed method provides also increasedrobustness in case of imperfect knowledge of the covariance matrix.

DFT-Based Channel Estimation for Holographic MIMO