5 papers
Near-field channel estimation via wavefront parameterization
Heedong Do, Namyoon Lee, Angel Lozano
This paper deals with the estimation of multiantenna channels in the line-of-sight conditions that are prevalent in the near field. By expressing the curved wavefront as a polynomi…
Transformer-Based Nonlinear Transform Coding for Multi-Rate CSI Compression in MIMO-OFDM Systems
Bumsu Park, Heedong Do, Namyoon Lee
We propose a novel approach for channel state information (CSI) compression in multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems, where…
Multidimensional Polynomial Phase Estimation
Heedong Do, Namyoon Lee, Angel Lozano
An estimation method is presented for polynomial phase signals, i.e., those adopting the form of a complex exponential whose phase is polynomial in its indices. Transcending the sc…
Multi-Rate Variable-Length CSI Compression for FDD Massive MIMO
Bumsu Park, Heedong Do, Namyoon Lee
For frequency-division-duplexing (FDD) systems, channel state information (CSI) should be fed back from the user terminal to the base station. This feedback overhead becomes proble…
Hybrid Arrays: How Many RF Chains Are Required to Prevent Beam Squint?
Heedong Do, Namyoon Lee, Robert W. Heath +1
With increasing frequencies, bandwidths, and array apertures, the phenomenon of beam squint arises as a serious impairment to beamforming. Fully digital arrays with true time delay…