Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exploiting Known Interference as Green Signal Power for Downlink
  Beamforming Optimization   We propose a data-aided transmit beamforming scheme for the multi-user
multiple-input-single-output (MISO) downlink channel. While conventional
beamforming schemes aim at the minimization of the transmit power subject to
suppressing interference to guarantee quality of service (QoS) constraints,
here we use the knowledge of both data and channel state information (CSI) at
the transmitter to exploit, rather than suppress, constructive interference.
More specifically, we design a new precoding scheme for the MISO downlink that
minimizes the transmit power for generic phase shift keying (PSK) modulated
signals. The proposed precoder reduces the transmit power compared to
conventional schemes, by adapting the QoS constraints to accommodate
constructive interference as a source of useful signal power. By exploiting the
power of constructively interfering symbols, the proposed scheme achieves the
required QoS at lower transmit power. We extend this concept to the signal to
interference plus noise ratio (SINR) balancing problem, where higher SINR
values compared to the conventional SINR balancing optimization are achieved
for given transmit power budgets. In addition, we derive equivalent virtual
multicast formulations for both optimizations, both of which provide insights
of the optimal solution and facilitate the design of a more efficient solver.
Finally, we propose a robust beamforming technique to deal with imperfect CSI,
that also reduces the transmit power over conventional techniques, while
guaranteeing the required QoS. Our simulation and analysis show significant
power savings for small scale MISO downlink channels with the proposed
data-aided optimization compared to conventional beamforming optimization.

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The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
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The categories of this paper are: acc-phys
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The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
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The categories of this paper are: cmp-lg
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The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
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The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
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The categories of this paper are: funct-an
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The categories of this paper are: nucl-ex