@article{oai:air.repo.nii.ac.jp:00005882,
author = {Koloko, Labson and Obara, Hitoshi and Kumagai, Seiji},
issue = {20},
journal = {Electronics Letters},
month = {Sep},
note = {Two-stage switch networks are an emerging design option for relatively small-capacity space switches. They are classified into two categories: folded and unfolded. Although folded switches have been well studied, research on unfolded two-stage switch networks (UTSNs) remains limited. Here, non-blocking UTSNs are considered. First, a new UTSN design is presented that consists of input and output switch modules (ISMs and OSMs) using bidirectional switching techniques. The proposed UTSN is represented by B(n, m, r), where n, m, and r denote the number of input ports of the ISM, number of OSMs, and number of ISMs, respectively. Second, the maximum number of rearrangements for B(n, n, r) is proved to be L(r-1)/2(n-1) RIGHT FLOOR in general, whereas it is limited to two when n >= r. The strictly non-blocking condition for B(n, m, r) to be m >= n + 1 is also determined. Finally, it is shown that the switch hardware complexity becomes minimal at n=N/2 and saturates at N-2/2 as N -> infinity.},
pages = {776--778},
title = {Structure and non-blocking properties of bidirectional unfolded two-stage switches},
volume = {57},
year = {2021}
}