Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Inverse LDM' and LU Factorizations of a Partitioned Matrix with the
  Square-root and Division Free Version for V-BLAST   This letter proposes the inverse LDM' and LU factorizations of a matrix
partitioned into 2x2 blocks, which include the square-root and division free
version. The proposed squareroot and division free inverse LDM' factorization
is applied to compute the initial estimation error covariance matrix Q for the
recursive V-BLAST algorithm, which can save K-1 divisions (where K is the
number of transmit antennas), and requires about the same computational
complexity as the corresponding algorithm to compute Q in the existing
recursive V-BLAST algorithm [8], [9]. The proposed square-root and division
free inverse LDM' factorization can also be applied to propose the square-root
and division free implementation for the squareroot V-BLAST algorithm in [5],
where the wide-sense Givens rotation in [14] is utilized. With respect to the
existing squareroot V-BLAST algorithms [5], [6], the proposed square-root and
division free V-BLAST algorithm requires about the same computational
complexity, and can avoid the square-root and division operations.

7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph