Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Message Passing Algorithm for Distributed Downlink Regularized
  Zero-forcing Beamforming with Cooperative Base Stations   Base station (BS) cooperation can turn unwanted interference to useful signal
energy for enhancing system performance. In the cooperative downlink,
zero-forcing beamforming (ZFBF) with a simple scheduler is well known to obtain
nearly the performance of the capacity-achieving dirty-paper coding. However,
the centralized ZFBF approach is prohibitively complex as the network size
grows. In this paper, we devise message passing algorithms for realizing the
regularized ZFBF (RZFBF) in a distributed manner using belief propagation. In
the proposed methods, the overall computational cost is decomposed into many
smaller computation tasks carried out by groups of neighboring BSs and
communications is only required between neighboring BSs. More importantly, some
exchanged messages can be computed based on channel statistics rather than
instantaneous channel state information, leading to significant reduction in
computational complexity. Simulation results demonstrate that the proposed
algorithms converge quickly to the exact RZFBF and much faster compared to
conventional methods.

8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an