Extremely large-scale massive multiple-input multiple-output (MIMO) has shown considerable potential in future mobile communications. However, the use of extremely large aperture arrays has led to near-field and spatial non-stationary channel conditions, which result in changes to transceiver design and channel state information that should be acquired. This letter focuses on the channel estimation problem and describes the non-stationary channel through mapping between subarrays and scatterers. We propose subarray-wise and scatterer-wise channel estimation methods to estimate the near-field non-stationary channel from the view of subarray and scatterer, respectively. Numerical results demonstrate that subarray-wise method can derive accurate channel estimation results with low complexity, whereas the scatterer-wise method can accurately position the scatterers and identify almost all the mappings between subarrays and scatterers.
@article{arxiv.1910.05432,
title = {Channel Estimation for Extremely Large-Scale Massive MIMO Systems},
author = {Yu Han and Shi Jin and Chao-Kai Wen and Xiaoli Ma},
journal= {arXiv preprint arXiv:1910.05432},
year = {2019}
}