Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cascaded Orthogonal Space-Time Block Codes for Wireless Multi-Hop Relay
  Networks   Distributed space-time block coding is a diversity technique to mitigate the
effects of fading in multi-hop wireless networks, where multiple relay stages
are used by a source to communicate with its destination. This paper proposes a
new distributed space-time block code called the cascaded orthogonal space-time
block code (COSTBC) for the case where the source and destination are equipped
with multiple antennas and each relay stage has one or more single antenna
relays. Each relay stage is assumed to have receive channel state information
(CSI) for all the channels from the source to itself, while the destination is
assumed to have receive CSI for all the channels. To construct the COSTBC,
multiple orthogonal space-time block codes are used in cascade by the source
and each relay stage. In the COSTBC, each relay stage separates the
constellation symbols of the orthogonal space-time block code sent by the
preceding relay stage using its CSI, and then transmits another orthogonal
space-time block code to the next relay stage. COSTBCs are shown to achieve the
maximum diversity gain in a multi-hop wireless network with flat Rayleigh
fading channels. Several explicit constructions of COSTBCs are also provided
for two-hop wireless networks with two and four source antennas and relay
nodes. It is also shown that COSTBCs require minimum decoding complexity thanks
to the connection to orthogonal space-time block codes.

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The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
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The categories of this paper are: stat
14
The categories of this paper are: math-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: solv-int
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The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin
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The categories of this paper are: chao-dyn
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-th
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The categories of this paper are: econ
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The categories of this paper are: gr-qc