Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Examples of usage of nearfield acoustic holography methods for far field
  estimations: Part 1. CW signals   The paper is devoted to the usage of nearfield acoustic holography methods
for estimating far field of the object. An experiment was carried out in
anechoic chamber. First, acoustic filed was recorded in a plane that was close
to source. This signals records were used to reconstruct the far field by
computation routines. Second, the signal in the far field is measured and the
results are compared. Several methods are tested and research on possible
reduction of the microphone array size is carried out. The most significant
reduction of the measurement facility complexity is usage a linear array in
stead of the planar array that is made possible due to introduced computation
routines

29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con