Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Polar-Precoding: A Unitary Finite-Feedback Transmit Precoder for
  Polar-Coded MIMO Systems   We propose a unitary precoding scheme, namely polar-precoding, to improve the
performance of polar-coded MIMO systems. In contrast to the traditional design
of MIMO precoding criteria, the proposed polar-precoding scheme relies on the
\emph{polarization criterion}. In particular, the precoding matrix design
comprises two steps. After selecting a basic matrix for maximizing the capacity
in the first step, we design a unitary matrix for maximizing the polarization
effect among the data streams without degrading the capacity. Our simulation
results show that the proposed polar-precoding scheme outperforms the
state-of-the-art DFT precoding scheme.

28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
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The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
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The categories of this paper are: stat
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The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat