Diagnosing crosstalk faults in a class of dilated blocking optical multistage interconnection networks
Optical Multistage Interconnection Networks (OMINs), which are constructed by photonic switches, have been studied extensively as an important interconnecting scheme for communication and parallel computing systems. A basic element of photonic switching network is a 22 directional coupler with two inputs and two outputs. A crosstalk occurs, when two signal channels interact with each other, caused by the improper control of voltage, temperature and polarization along with the aging of the material. In this paper, we will focus on a specific architecture called the Dilated Blocking Networks. The characteristic of dilated blocking networks, such as Dilated Omega Network (DON), is that only one possible path can be established between any input-output pair. The two-level diagnosis algorithm is proposed to satisfy the need of this architecture. The first-order crosstalk will be detected and located in the first level. In addition, the number of unused photonic switches grows in ?(N2) as the size of network increases in NN during the diagnosing crosstalk algorithm. By this property, we speed up the test by paralleling two first-order crosstalk faults at the first-level algorithm (we call it as disjoint faults). The second-level algorithm will diagnose the second- or higher-order crosstalk as well as all crosstalks will be diagnosed. Finally, we apply the diagnosing algorithm to other dilated photonic isomorphic topologies, say, Dilated Baseline Network and Dilated Banyan Network.
photonic switching directional coupler disjoint faults isomorphic topology diagnosing fault algorithm