Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Doppler Spread Estimation by Subspace Tracking for OFDM Systems   This paper proposes a novel maximum Doppler spread estimation algorithm for
OFDM systems with the comb-type pilot pattern. By tracking the drifting delay
subspace of the multipath channel, the time correlation function is measured at
a high accuracy, which accordingly improves the estimation accuracy of the
maximum Doppler spread considerably.

30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex