Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Distributed Massive MIMO Channel Estimation and Channel Database
  Assistance   Due to the low per-antenna SNR and high signaling overhead, channel
estimation is a major bottleneck in Massive MIMO systems. Spatial constraints
can improve estimation performance by exploiting sparsity. Solutions exist for
far field - beam domain channel estimation based on angle of arrival
estimation. However, there is no equivalent solution for near field and
distributed MIMO spatial channel estimation. We present a solution- source
domain channel estimation- that is based on source location estimation. We
extend this to employ a "Channel Database" incorporating information about the
physical scattering environment into channel estimation. We present methods for
generation, storage and usage of the Channel Database to assist localization
and communication.

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The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
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The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
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The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn
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The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas