Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatial Diversity in Molecular Communications   In this work, spatial diversity techniques in the area of multiple-input
multiple-output (MIMO) diffusion-based molecular communications (DBMC) are
investigated. For transmitter-side spatial coding, Alamouti-type coding and
repetition MIMO coding are proposed and analyzed. At the receiver-side,
selection diversity, equal-gain combining, and maximum-ratio combining are
studied as combining strategies. Throughout the numerical analysis, a
symmetrical $2\times 2$ MIMO-DBMC system is assumed. Furthermore, a trained
artificial neural network is utilized to acquire the channel impulse responses.
The numerical analysis demonstrates that it is possible to achieve a diversity
gain in molecular communications. In addition, it is shown that for MIMO-DBMC
systems repetition MIMO coding is superior to Alamouti-type coding.

29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom