Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Grassmannian Beamforming for MIMO-OFDM Systems with Frequency and
  Spatially Correlated Channels Using Huffman Coding   Multiple input multiple output (MIMO) precoding is an efficient scheme that
may significantly enhance the communication link. However, this enhancement
comes with a cost. Many precoding schemes require channel knowledge at the
transmitter that is obtained through feedback from the receiver. Focusing on
the natural common fusion of orthogonal frequency division multiplexing (OFDM)
and MIMO, we exploit the channel correlation in the frequency and spatial
domain to reduce the required feedback rate in a frequency division duplex
(FDD) system. The proposed feedback method is based on Huffman coding and is
employed here for the single stream case. The method leads to a significant
reduction in the required feedback rate, without any loss in performance. The
proposed method may be extended to the multi-stream case.

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The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
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The categories of this paper are: alg-geom
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The categories of this paper are: eess
4
The categories of this paper are: cond-mat