Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatial Lattice Modulation for MIMO Systems   This paper proposes spatial lattice modulation (SLM), a spatial modulation
method for multipleinput-multiple-output (MIMO) systems. The key idea of SLM is
to jointly exploit spatial, in-phase, and quadrature dimensions to modulate
information bits into a multi-dimensional signal set that consists oflattice
points. One major finding is that SLM achieves a higher spectral efficiency
than the existing spatial modulation and spatial multiplexing methods for the
MIMO channel under the constraint ofM-ary pulseamplitude-modulation (PAM) input
signaling per dimension. In particular, it is shown that when the SLM signal
set is constructed by using dense lattices, a significant signal-to-noise-ratio
(SNR) gain, i.e., a nominal coding gain, is attainable compared to the existing
methods. In addition, closed-form expressions for both the average mutual
information and average symbol-vector-error-probability (ASVEP) of generic SLM
are derived under Rayleigh-fading environments. To reduce detection complexity,
a low-complexity detection method for SLM, which is referred to as lattice
sphere decoding, is developed by exploiting lattice theory. Simulation results
verify the accuracy of the conducted analysis and demonstrate that the proposed
SLM techniques achieve higher average mutual information and lower ASVEP than
do existing methods.

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The categories of this paper are: nucl-th
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The categories of this paper are: astro-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
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The categories of this paper are: stat
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg